Composite sheet for protective film formation

Abstract

Provided is a composite sheet for protective film formation, which comprises a substrate, and has an energy ray-curable adhesive layer and a protective film-forming film stacked in this order and in contact with each other on one face of the substrate, the gel fraction of the adhesive layer being 80% or more, or the gel fraction of the adhesive layer being 20% or more and less than 80%, and the protective film-forming film having a glass transition temperature of 3°C or more.

Description

TECHNICAL FIELD

[0001] The present application relates to a composite sheet for protective film formation. This application claims priority from Japanese Patent Application No. 2019-158473 filed on August 30, 2019, and the content thereof is incorporated herein. BACKGROUND

[0002] In the manufacturing process of a semiconductor device, a protective film is sometimes used to protect a workpiece that needs to be processed in order to obtain a target object.

[0003] For example, in the manufacturing of a semiconductor device to which a mounting method called a face down method is applied, a semiconductor wafer having an electrode such as a bump on a circuit surface is used as a workpiece, and in order to suppress the generation of cracks in the semiconductor wafer or a semiconductor chip that is a divided product thereof, a protective film is sometimes used to protect the back surface of the semiconductor wafer or the semiconductor chip on the opposite side from the circuit surface. In addition, in the manufacturing process of a semiconductor device, a semiconductor device panel described later is used as a workpiece, and in order to suppress the occurrence of bending or cracking on the panel, a protective film is sometimes used to protect any part of the panel.

[0004] In order to form the above-described protective film, for example, a composite sheet for protective film formation is used, which is configured by providing a support sheet, and further providing a protective film formation film for forming a protective film on one surface of the support sheet.

[0005] The protective film formation film can function as a protective film by being cured, or can function as a protective film in an uncured state. In addition, the support sheet can be used to fix a workpiece provided with the protective film formation film or a cured product thereof. For example, when a semiconductor wafer is used as a workpiece, the support sheet can be used as a dicing sheet necessary when the semiconductor wafer is divided into semiconductor chips. As the support sheet, for example, a support sheet provided with a base material and an adhesive layer provided on one surface of the base material, a support sheet composed only of a base material, and the like can be exemplified. When the support sheet is provided with an adhesive layer, the adhesive layer is disposed between the base material and the protective film formation film in the composite sheet for protective film formation.

[0006] When the above-described composite sheet for protective film formation is used, first, the protective film formation film in the composite sheet for protective film formation is attached to a target position of a workpiece.

[0007] Then, the workpiece in the state of the above-mentioned composite sheet having the protective film forming composite sheet is processed as needed, whereby a workpiece processed product is obtained. For example, when a semiconductor wafer is used as the workpiece, after the protective film forming composite sheet is attached to the back surface of the workpiece with the protective film forming film therein, at respective appropriate timings, the following are appropriately performed: formation of a protective film based on curing of the protective film forming film, cutting of the protective film forming film or the protective film, division (dicing) from the semiconductor wafer to semiconductor chips, picking up of the semiconductor chips with the protective film forming film or the protective film on the back surface from the support sheet, and the like. When the semiconductor chips with the protective film forming film have been picked up, the semiconductor chips with the protective film forming film are made into semiconductor chips with the protective film by curing of the protective film forming film, and finally semiconductor devices are manufactured using the semiconductor chips with the protective film.

[0008] Patent Document 1 discloses a dicing tape-integrated semiconductor back surface film in which a flip chip type semiconductor back surface film is stacked on a dicing tape in which an adhesive is stacked on a base material, and the flip chip type semiconductor back surface film is formed of a thermosetting resin component and a thermoplastic resin component having a glass transition temperature of 25°C or higher and 200°C or lower.

[0009] Prior Art Documents

[0010] Patent Documents

[0011] Patent Document 1: Japanese Patent No. 5479991 SUMMARY

[0012] Technical Problem to be Solved by the Invention

[0013] As such a protective film forming composite sheet, in addition to the composite sheet having the support sheet including the adhesive layer cured by heating, a support sheet having an adhesive layer cured by irradiation of energy rays such as ultraviolet rays is also used.

[0014] An energy ray-curable adhesive is generally composed of a photopolymerizable resin and a photopolymerization initiator, and the photopolymerizable resin is crosslinked and cured by the photopolymerization initiator by irradiation of energy rays. However, before the energy ray-curing, there is a problem that the photopolymerizable resin and the photopolymerization initiator, which are not crosslinked, move from the adhesive layer to the protective film-forming film, or the components of the protective film-forming film move to the adhesive layer. If such a component movement occurs, the adhesive layer after the energy ray irradiation is not sufficiently cured or crosslinking occurs between the adhesive layer and the protective film-forming film, and thus when a semiconductor chip with a cured protective film (a semiconductor chip with a protective film) is picked up from a support sheet, there is a possibility that the semiconductor chip with a protective film cannot be peeled from the support sheet or peeling occurs between the semiconductor chip and the protective film.

[0015] An object of the present application is to provide a protective film-forming composite sheet which has a substrate, and an energy ray-curable adhesive layer and a protective film-forming film are sequentially and in contact with each other laminated on one surface of the substrate, and when a semiconductor chip with a protective film is picked up from a support sheet, peeling does not occur between the semiconductor chip and the protective film, and the semiconductor chip with a protective film can be peeled from the support sheet.

[0016] Technical means for solving the technical problem

[0017] The present application provides a protective film-forming composite sheet which has a substrate, and an energy ray-curable adhesive layer and a protective film-forming film are sequentially and in contact with each other laminated on one surface of the substrate, and a gel fraction of the adhesive layer is 80% or more.

[0018] The present application provides a protective film-forming composite sheet which has a substrate, and an energy ray-curable adhesive layer and a protective film-forming film are sequentially and in contact with each other laminated on one surface of the substrate, and a gel fraction of the adhesive layer is 20% or more and less than 80%, and a glass transition temperature (Tg) of the protective film-forming film is 3°C or more.

[0019] It is preferable that the protective film-forming film of the protective film-forming composite sheet of the present application has a loss modulus at 23°C of 3 MPa or more.

[0020] The protective film-forming film of the protective film-forming composite sheet of the present application contains a filler material (D), and it is preferable that the content of the filler material (D) is 50% by mass or more with respect to the total mass of the protective film-forming film.

[0021] Effects of the Invention

[0022] According to the present invention, a composite sheet for forming a protective film is provided, which includes a substrate and an energy-curable adhesive layer and a protective film forming film are sequentially and in contact with each other on one side of the substrate. When a semiconductor chip with a protective film is picked up from a support sheet, no peeling occurs between the semiconductor chip and the protective film, and the semiconductor chip with a protective film can be peeled off from the support sheet. Attached Figure Description

[0023] Figure 1 A cross-sectional view illustrating an example of a composite sheet for forming a protective film according to one embodiment of the present invention.

[0024] Figure 2 A cross-sectional view illustrating another example of a composite sheet for forming a protective film according to one embodiment of the present invention.

[0025] Figure 3 This is a cross-sectional view illustrating an example of a method for manufacturing a semiconductor chip with a protective film when using a composite sheet for forming a protective film according to one embodiment of the present invention.

[0026] Figure 4 This is a cross-sectional view illustrating an example of a method for manufacturing a semiconductor chip with a protective film when using a composite sheet for forming a protective film according to one embodiment of the present invention.

[0027] Figure 5 This is a cross-sectional view illustrating an example of a method for manufacturing a semiconductor chip with a protective film when using a composite sheet for forming a protective film according to one embodiment of the present invention.

[0028] Figure 6 This is a cross-sectional view illustrating an example of a method for manufacturing a semiconductor chip with a protective film when using a composite sheet for forming a protective film according to one embodiment of the present invention.

[0029] Figure 7 This is a cross-sectional view illustrating an example of a method for manufacturing a semiconductor chip with a protective film when using a composite sheet for forming a protective film according to one embodiment of the present invention.

[0030] Explanation of reference numerals in the attached figures

[0031] 101, 102: composite sheet for protective film formation; 1011: composite sheet for protective film formation on which the film for protective film formation has been cured; 1012: composite sheet for protective film formation on which the film for protective film formation has been cured and on which characters have been printed; 10: support sheet; 10a: one face (first face) of the support sheet; 13, 23: film for protective film formation; 13': protective film (cured product of the film for protective film formation); 130': cut protective film (cured product of the cut film for protective film formation); 9: semiconductor wafer; 9a: circuit formation face of the semiconductor wafer; 9b: back face of the semiconductor wafer; 9': semiconductor chip; L: laser. DETAILED DESCRIPTION

[0032] Composite sheet for protective film formation

[0033] The composite sheet for protective film formation of the first embodiment of the present application has a substrate, and an energy ray-curable adhesive layer and a film for protective film formation are sequentially and in contact with each other laminated on one face of the substrate, and the gel fraction of the adhesive layer is 80% or more.

[0034] By setting the gel fraction of the energy ray-curable adhesive of the adhesive layer of the composite sheet for protective film formation to the lower limit value or more, the mutual movement of components between the energy ray-curable adhesive layer and the film for protective film formation before energy ray curing is suppressed, and peeling between the semiconductor chip and the protective film does not occur when the semiconductor chip with the protective film is picked up from the support sheet, and the semiconductor chip with the protective film can be peeled from the support sheet.

[0035] The composite sheet for protective film formation of the second embodiment of the present application has a substrate, and an energy ray-curable adhesive layer and a film for protective film formation are sequentially and in contact with each other laminated on one face of the substrate, and the gel fraction of the adhesive layer is 20% or more and less than 80%, and the glass transition temperature of the film for protective film formation is 3°C or more.

[0036] If the glass transition temperature of the film for protective film formation is 3°C or more, even if the gel fraction of the adhesive layer before energy ray curing is 20% or more and less than 80%, the mutual movement of components between the energy ray-curable adhesive layer and the film for protective film formation before energy ray curing is suppressed, and peeling between the semiconductor chip and the protective film does not occur when the semiconductor chip with the protective film is picked up from the support sheet, and the semiconductor chip with the protective film can be peeled from the support sheet.

[0037] The loss modulus E" of the protective film forming film of the protective film forming composite sheet of the present application at 23°C is preferably 3 MPa or more, more preferably 5 MPa or more, and further preferably 10 MPa or more, for example, can be any one range of 17 MPa or more and 45 MPa or more. By making the loss modulus of the protective film forming film at 23°C be the lower limit value or more, the low molecular components such as the photopolymerizable resin or the photopolymerization initiator of the energy ray-curable adhesive are inhibited from moving to the protective film forming film.

[0038] The loss modulus E" of the protective film forming film at 23°C is preferably 100 MPa or less, and more preferably 90 MPa or less. By making the loss modulus E" of the protective film forming film at 23°C be the upper limit value or less, the operability of the protective film forming film to be attached to the workpiece is improved.

[0039] The protective film forming film of the protective film forming composite sheet of the present application contains the filler material (D), and in the protective film forming film, the content of the filler material (D) is preferably 50% by mass or more, more preferably 53% by mass or more, and further preferably 55% by mass or more, for example, can be 60% by mass, with respect to the total mass of the protective film forming film. In the protective film forming film, by making the content of the filler material (D) be the lower limit value or more with respect to the total mass of the protective film forming film, the low molecular components such as the photopolymerizable resin or the photopolymerization initiator of the energy ray-curable adhesive are further inhibited from moving to the protective film forming film.

[0040] In the protective film forming film, the content of the filler material (D) is preferably 90% by mass or less, and more preferably 80% by mass or less, with respect to the total mass of the protective film forming film. In the protective film forming film, by making the content of the filler material (D) be the upper limit value or less with respect to the total mass of the protective film forming film, the adhesion of the protective film forming film to the workpiece is improved.

[0041] The protective film forming film in the protective film forming composite sheet of the present embodiment can be curable or non-curable.

[0042] In the present specification, even after the protective film forming film is cured, as long as the laminated structure of the support sheet and the cured product of the protective film forming film is maintained, the laminated structure is referred to as a "protective film forming composite sheet".

[0043] Further, in the present specification, only when described as an "adhesive layer" means a "pre-cured adhesive layer".

[0044] The protective film forming composite sheet of the present embodiment can have other layers that are not any one of the substrate, the adhesive layer, the protective film forming film, and the release film, within a range that does not impair the effects of the present application.

[0045] The kind of the other layer is not particularly limited and can be arbitrarily selected according to the purpose.

[0046] The arrangement position, shape, size, and the like of the other layer can be arbitrarily selected according to the kind thereof and are not particularly limited, but it is preferable that the size of the protective film forming film be larger than the workpiece.

[0047] The thickness of the workpiece to which the protective film forming composite sheet of the present embodiment is attached is not particularly limited, and from the viewpoint of making it easier to process (for example, to divide) the workpiece product described later, it is preferable that the thickness be 30 to 1000 μm, and more preferably 70 to 400 μm.

[0048] The protective film forming composite sheet of the present embodiment is used to be attached to a workpiece, and as a preferable workpiece to which it is attached, for example, a semiconductor wafer can be cited. The protective film forming composite sheet is preferably used to be attached to the back surface of a semiconductor wafer.

[0049] Figure 1 A cross-sectional view schematically showing one example of the protective film forming composite sheet of one embodiment of the present application.

[0050] The protective film forming composite sheet 101 shown therein is configured by having the support sheet 10 and the protective film forming film 13 provided on one surface (in the present specification, sometimes referred to as "first surface") 10a of the support sheet 10.

[0051] The support sheet 10 is configured by having the substrate 11 and the adhesive layer 12 provided on one surface 11a of the substrate 11. In the protective film forming composite sheet 101, the adhesive layer 12 is arranged between the substrate 11 and the protective film forming film 13.

[0052] That is, the protective film forming composite sheet 101 is configured by sequentially stacking the substrate 11, the adhesive layer 12, and the protective film forming film 13 in the thickness direction thereof.

[0053] The surface (in the present specification, sometimes referred to as "first surface") 10a of the support sheet 10 on the side of the protective film forming film 13 and the surface (in the present specification, sometimes referred to as "first surface") 12a of the adhesive layer 12 on the side opposite to the substrate 11 side are the same.

[0054] The protective film forming composite sheet 101 further has the jig adhesive layer 16 and the release film 15 provided on the protective film forming film 13.

[0055] In the protective film forming composite sheet 101, the protective film forming film 13 is laminated on the entire surface or almost the entire surface of the first surface 12a of the adhesive layer 12, and the jig adhesive layer 16 is laminated on a portion of the surface (in this specification, sometimes referred to as "first surface") 13a of the protective film forming film 13 on the opposite side from the adhesive layer 12, that is, a region in the vicinity of the peripheral edge portion. Further, on a region in the first surface 13a of the protective film forming film 13 on which the jig adhesive layer 16 is not laminated, and on the surface (in this specification, sometimes referred to as "first surface") 16a of the jig adhesive layer 16 on the opposite side from the protective film forming film 13, the release film 15 is laminated.

[0056] The protective film forming composite sheet of the present embodiment is not limited to the protective film forming composite sheet 101, and the release film (for example, the release film 15 shown in Figure 1 The protective film forming composite sheet of the present embodiment can have a release film or can not have a release film, regardless of the configuration of the release film.

[0057] The jig adhesive layer 16 is used to fix the protective film forming composite sheet 101 to a jig such as a ring frame.

[0058] The jig adhesive layer 16 can have, for example, a single-layer structure including an adhesive component, or can have a multi-layer structure in which a layer including an adhesive component is laminated on both surfaces of a sheet as a core material.

[0059] The protective film forming composite sheet 101 is used in the following manner: in a state in which the release film 15 is removed, the first surface 13a of the protective film forming film 13 is attached to an arbitrary position of a workpiece (not shown), and further, the first surface 16a of the jig adhesive layer 16 is attached to a jig such as a ring frame.

[0060] Figure 2 A cross-sectional view schematically showing another example of the protective film forming composite sheet of one embodiment of the present application.

[0061] In addition, in Figure 2 In the drawings that follow, the same reference signs are assigned to the same constituent elements as those shown in the already explained drawings, and detailed description thereof is omitted.

[0062] The protective film forming composite sheet 102 shown in FIG. 12 is the same as the protective film forming composite sheet 101 shown in Figure 1

[0063] ​More specifically, in the protective film forming composite sheet 102, the protective film forming film 23 is laminated on a part of the first face 12a of the adhesive layer 12, that is, on a region on the central side in the width direction (left-right direction in Figure 2 Furthermore, the region on the first face 12a of the adhesive layer 12 on which the protective film forming film 23 is not laminated, that is, the region near the periphery, is laminated with the jig adhesive layer 16. Also, the first face 23a of the protective film forming film 23 on the opposite side from the adhesive layer 12 (in this specification, sometimes referred to as the "first face") and the first face 16a of the jig adhesive layer 16 are laminated with the release film 15.

[0064] Thus far, for the protective film forming composite sheet provided with a jig adhesive layer, the protective film forming composite sheet 101 shown in Figure 1 and the protective film forming composite sheet 102 shown in Figure 2 have been shown, but these are merely one example of other protective film forming composite sheets provided with a jig adhesive layer.

[0065] The protective film forming composite sheet provided with a jig adhesive layer described above is used in a manner in which the first face of the jig adhesive layer is attached to a jig such as a ring-shaped frame.

[0066] Thus, regardless of the form of the support sheet and the protective film forming film, the protective film forming composite sheet of the present embodiment can be provided with a jig adhesive layer.

[0067] As a protective film forming composite sheet not provided with a jig adhesive layer, for example, the protective film forming composite sheet not provided with the jig adhesive layer 16 in the protective film forming composite sheet 102 shown in Figure 2 may be cited. However, this protective film forming composite sheet is merely one example of other protective film forming composite sheets not provided with a jig adhesive layer.

[0068] In Figure 1 and Figure 2 , as the members that constitute the protective film forming composite sheet, a substrate, an adhesive layer, a protective film forming film, and a release film are shown, but the protective film forming composite sheet of the present embodiment can also be provided with the other layer not belonging to any of the above-described layers.

[0069] When the protective film forming composite sheet shown in Figure 1 and Figure 2 is provided with the other layer, the position in which it is disposed is not particularly limited except between the adhesive layer and the protective film forming film.

[0070] In the protective film forming composite sheet of the present embodiment, the size and shape of each layer can be arbitrarily selected according to the purpose.

[0071] Next, the constitution of the composite sheet for protective film formation will be described in detail.

[0072] ■Support sheet

[0073] The support sheet of one embodiment of the present application can be used to form a composite sheet for protective film formation by being stacked on the film for protective film formation, for example, as described later.

[0074] The support sheet of this embodiment can be used to fix a workpiece provided with a film for protective film formation or a cured product thereof at any position, as described later.

[0075] As the workpiece, for example, a semiconductor wafer, a semiconductor device panel, or the like can be given. A semiconductor device panel is used in the process of manufacturing a semiconductor device, and as a specific example, a semiconductor device panel provided with a plurality of electronic components on one circuit board can be given.

[0076] In this specification, an article obtained by processing a workpiece is referred to as a "workpiece processed article". For example, when the workpiece is a semiconductor wafer, a semiconductor chip can be given as a workpiece processed article.

[0077] For example, when the workpiece is a semiconductor wafer, the support sheet of this embodiment can be used to fix a semiconductor wafer provided with a film for protective film formation or a cured product thereof on the back surface.

[0078] As the support sheet, for example, a support sheet provided with a base material and an adhesive layer provided on one surface of the base material can be given. When the support sheet is provided with an adhesive layer, in the composite sheet for protective film formation described later, the adhesive layer is arranged between the base material and the film for protective film formation.

[0079] When a support sheet provided with a base material and an adhesive layer is used, in the composite sheet for protective film formation, the adhesion or the close contact between the support sheet and the film for protective film formation can be easily adjusted.

[0080] When a support sheet composed only of a base material is used, the composite sheet for protective film formation can be manufactured at low cost.

[0081] When a support sheet provided with a base material and an adhesive layer is used, a new function can be given to the support sheet or the composite sheet for protective film formation. Furthermore, compared with the case of the above-described adhesive layer, the adhesion or the close contact between the support sheet and the film for protective film formation can be more easily adjusted.

[0082] ■Base material

[0083] The base material is in a sheet shape or a film shape, and as a material constituting the base material, for example, various resins can be given.

[0084] As the resin, for example, a polyolefin such as low-density polyethylene (LDPE), polypropylene (PP), an ethylene-methacrylic acid copolymer (EMAA), polyvinyl chloride (PVC), a polyester such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate (PBT), a polyether sulfone, a polyacrylate, polycarbonate (PC), or the like can be exemplified.

[0085] The resin constituting the base material can be only one kind, or two or more kinds, and the combination and ratio thereof can be arbitrarily selected.

[0086] The base material can be constituted by one layer (single layer), or by a plurality of layers of two or more layers, and when constituted by a plurality of layers, the plurality of layers can be the same as each other, or different from each other, and the combination of the plurality of layers is not particularly limited.

[0087] In the present specification, not only the base material, but also "the plurality of layers can be the same as each other, or different from each other" means "all the layers can be the same, or all the layers can be different, or only a part of the layers can be the same", and further, "the plurality of layers are different from each other" means "at least one of the constituent material and the thickness of each layer is different from each other".

[0088] The thickness of the base material is preferably 50 to 300 μm, more preferably 60 to 140 μm, and particularly preferably 80 to 100 μm. By making the thickness of the base material in the above range, the flexibility of the composite sheet for forming a protective film, and the adhesion to a workpiece or a workpiece processed product are further improved.

[0089] Herein, the "thickness of the base material" means the thickness of the entire base material, and for example, the thickness of a base material constituted by a plurality of layers means the total thickness of all the layers constituting the base material.

[0090] The base material is preferably a base material having high thickness accuracy, that is, a base material in which the unevenness of the thickness is suppressed regardless of the site. Among the above-mentioned constituent materials, as a material that can be used to constitute the above-mentioned base material having high thickness accuracy, for example, a polyolefin, polyethylene terephthalate, or the like can be exemplified.

[0091] The base material can contain, in addition to the above-mentioned resin and the like as the main constituent material, a filler, a colorant, an antistatic agent, an antioxidant, an organic lubricant, a catalyst, a softening agent (plasticizer), and the like, as well as various known additives.

[0092] The base material can be transparent, or opaque, and can be colored, or can be vapor-deposited with other layers, within a range in which the energy ray-curing property of the adhesive layer is ensured.

[0093] For example, when the film for forming a protective film has an energy ray-curing property, it is preferable that the base material transmit the energy ray.

[0094] For example, in order to optically inspect the protective film forming film in the protective film forming composite sheet through the substrate, the substrate is preferably transparent.

[0095] In order to improve the adhesion of the substrate to a layer (e.g., an adhesive layer, a protective film forming film, etc.) provided on the substrate, a surface can be subjected to a sandblasting treatment, a concave-convex treatment based on a solvent treatment, etc.; a corona discharge treatment, an electron beam irradiation treatment, a plasma treatment, an ozone-ultraviolet irradiation treatment, a flame treatment, a chromic acid treatment, a hot air treatment, etc. an oxidation treatment, etc. In addition, the surface of the substrate can be subjected to a primer treatment.

[0096] In addition, the substrate can have the following layers: an antistatic coating layer; a layer that prevents the substrate from adhering to other sheets or an adsorption table when the protective film forming composite sheet is stored in a stack; etc.

[0097] The substrate can be manufactured using a publicly known method. For example, a substrate containing a resin can be manufactured by molding a resin composition containing the resin.

[0098] ◎ Adhesive Layer

[0099] The adhesive layer is in a sheet or film shape and contains an adhesive.

[0100] As the adhesive, for example, an adhesive resin such as an acrylic resin, a urethane resin, a rubber-based resin, a silicone resin, an epoxy-based resin, a polyvinyl ether, a polycarbonate, an ester-based resin, etc. can be exemplified, and an acrylic resin is preferable.

[0101] In addition, in the present specification, an "adhesive resin" includes a resin having adhesiveness and a resin having cohesiveness. For example, the adhesive resin includes not only a resin having adhesiveness by itself, but also a resin exhibiting adhesiveness by simultaneous use with another component such as an additive or a resin exhibiting cohesiveness due to the presence of a trigger such as heat or water, etc.

[0102] The adhesive layer can be composed of one layer (single layer) or a plurality of layers of two or more layers, and when composed of a plurality of layers, the plurality of layers can be the same as or different from each other, and the combination of the plurality of layers is not particularly limited.

[0103] The thickness of the adhesive layer is preferably 1 to 14 μm, more preferably 2 to 12 μm, and for example, can be 3 to 8 μm. By making the thickness of the adhesive layer be the lower limit value or more, the effect of providing the adhesive layer can be more remarkably obtained. By making the thickness of the adhesive layer be the upper limit value or less, printing on the protective film forming film or a cured product thereof in the protective film forming composite sheet can be more favorably performed. Furthermore, the printing can be more favorably recognized from the outside of the protective film forming composite sheet through the support sheet.

[0104] In the present specification, the "thickness of the adhesive layer" refers to the thickness of the entire adhesive layer, and for example, the thickness of an adhesive layer composed of a plurality of layers refers to the total thickness of all the layers that constitute the adhesive layer.

[0105] In the present embodiment, the adhesive layer is formed using an energy ray-curable adhesive. That is, the adhesive layer is energy ray-curable. The energy ray-curable adhesive layer can easily adjust the physical properties before and after curing. For example, before picking up the semiconductor chips described later with the protective film or the semiconductor chips with the protective film forming film, the energy ray-curable adhesive layer can be cured, thereby making it easier to pick up these semiconductor chips.

[0106] In the present specification, the "energy ray" refers to a ray having an energy quantum in an electromagnetic wave or a charged particle beam, and as examples thereof, ultraviolet rays, radioactive rays, electron beams, and the like can be listed. For example, as the ultraviolet rays, irradiation can be performed by using a high-pressure mercury lamp, a fusion H lamp, a xenon lamp, a black light lamp, or an LED lamp or the like as an ultraviolet ray source. As the electron beam, an electron beam generated using an electron beam accelerator or the like can be irradiated.

[0107] Further, in the present specification, the "energy ray-curable" refers to a property of being cured by irradiation of an energy ray, and the "non-energy ray-curable" refers to a property of not being cured even if an energy ray is irradiated.

[0108] In the protective film forming composite sheet of the first embodiment, the gel fraction of the adhesive layer is 80% or more, preferably 85% or more, and more preferably 90% or more. By making the gel fraction of the adhesive layer 80% or more, the movement of components between the energy ray-curable adhesive layer before energy ray curing and the protective film forming film is inhibited, and when the semiconductor chips with the protective film are picked up from the support sheet, peeling does not occur between the semiconductor chips and the protective film, and the semiconductor chips with the protective film can be peeled from the support sheet.

[0109] In the protective film forming composite sheet of the second embodiment, the gel fraction of the adhesive layer is 20% or more and less than 80%, preferably 30% or more and less than 80%, and more preferably 40% or more and less than 80%. Even if the gel fraction of the adhesive layer is less than 80%, by making the glass transition temperature (Tg) of the protective film forming film described later 3°C or more, the movement of components between the energy ray-curable adhesive layer before energy ray curing and the protective film forming film is inhibited, and when the semiconductor chips with the protective film are picked up from the support sheet, peeling does not occur between the semiconductor chips and the protective film, and the semiconductor chips with the protective film can be peeled from the support sheet.

[0110] In the protective film forming composite sheet of the second embodiment, if the gel fraction of the adhesive layer is in the above range, the adhesive layer can be easily formed. If the gel fraction is less than 20%, the adhesive layer remains on the protective film forming sheet, and the reliability of the semiconductor chip with the protective film decreases.

[0111] The gel fraction of the adhesive layer can be measured using a known method. Specifically, it can be measured by the following method.

[0112] A release film prepared by forming a silicone resin release agent layer on one face of a polyethylene terephthalate substrate film (thickness 38 μm) was prepared. Then, the adhesive composition was applied to the release treatment face of the release film, and dried to form an adhesive layer having a thickness of 20 μm.

[0113] Then, the adhesive layer was cut to a size of 50 mm x 100 mm as a test sample, and wrapped with a nylon mesh (mesh size 200) of 100 mm x 150 mm to prepare a test piece. The mass Ml of the test sample itself was measured using a precision balance, and then the test piece was immersed in ethyl acetate (100 mL) at 25°C for 24 hours, and then taken out, dried at 120°C for 1 hour, and further conditioned at 23°C and a relative humidity of 50% for 1 hour. Then, the mass M2 of the test sample itself excluding the mass of the mesh of the test piece was measured using a precision balance. The gel fraction of the test sample (i.e., the adhesive layer) before energy ray irradiation was calculated by the following equation.

[0114] Gel fraction (%) of adhesive layer = (M2 / Ml) x 100

[0115] Adhesive composition

[0116] The adhesive layer can be formed using an adhesive composition containing an adhesive. For example, the adhesive composition is applied to the face on which the adhesive layer is to be formed, and dried as needed, whereby the adhesive layer can be formed at the target site. The content ratio of the components that do not vaporize at ordinary temperature to each other in the adhesive composition is usually the same as the content ratio of the components to each other in the adhesive layer. In the present specification, "ordinary temperature" means a temperature that is not particularly cooled or heated, i.e., a temperature as it is, and for example, a temperature of 15 to 25°C or the like can be mentioned.

[0117] The application of the adhesive composition can be performed using a known method, and for example, a method using various coaters such as an air knife coater, a blade coater, a bar coater, a gravure coater, a roll coater, a knife-over-roll coater, a curtain coater, a die coater, a doctor blade coater, a screen coater, a Meyer rod coater, a kiss coater, and the like can be mentioned.

[0118] The drying conditions of the adhesive composition are not particularly limited, but when the adhesive composition contains a solvent described later, heating drying is preferably performed. The adhesive composition containing a solvent is, for example, preferably dried at 70 to 130°C for 10 seconds to 5 minutes.

[0119] When the adhesive layer is provided on the substrate, for example, the adhesive layer can be layered on the substrate by coating the adhesive composition on the substrate and drying as needed. Further, when the adhesive layer is provided on the substrate, for example, the adhesive layer can be layered on the substrate by coating the adhesive composition on a release film, forming the adhesive layer on the release film as needed, and adhering the exposed surface of the adhesive layer to one surface of the substrate. The release film at this time is removed at any timing during the manufacturing process or the use process of the protective film forming composite sheet.

[0120] In the present application, the adhesive is energy ray-curable. As the energy ray-curable adhesive composition, for example, an adhesive composition (I-1) containing a non-energy ray-curable adhesive resin (I-1a) (hereinafter, sometimes abbreviated as "adhesive resin (I-1a)") and an energy ray-curable compound; an adhesive composition (I-2) containing an energy ray-curable adhesive resin (I-2a) (hereinafter, sometimes abbreviated as "adhesive resin (I-2a)") in which an unsaturated group is introduced into a side chain of the adhesive resin (I-1a); an adhesive composition (I-3) containing the adhesive resin (I-2a) and an energy ray-curable compound; and the like can be exemplified.

[0121] [Adhesive resin (I-1a)]

[0122] The adhesive resin (I-1a) in the adhesive composition (I-1), the adhesive composition (I-2), and the adhesive composition (I-3) (hereinafter, these adhesive compositions are collectively abbreviated as "adhesive composition (I-1) to (I-3)") is preferably an acrylic resin.

[0123] As the acrylic resin, for example, an acrylic polymer having at least a structural unit derived from an alkyl (meth)acrylate can be exemplified.

[0124] As the alkyl (meth)acrylate, for example, an alkyl (meth)acrylate in which the number of carbon atoms of the alkyl group constituting the alkyl ester is 1 to 20, and the alkyl group is preferably linear or branched, can be exemplified.

[0125] In addition, in the present specification, "(meth)acrylic acid" is a concept including "acrylic acid" and "methacrylic acid". The same applies to terms similar to (meth)acrylic acid, for example, "(meth)acryloyl" is a concept including "acryloyl" and "methacryloyl", and "(meth)acrylate" is a concept including "acrylate" and "methacrylate".

[0126] The acrylic acid polymer preferably further has a structural unit derived from a functional group-containing monomer in addition to the structural unit derived from the alkyl (meth)acrylate.

[0127] As the functional group-containing monomer, for example, a functional group-containing monomer capable of introducing an unsaturated group into a side chain of an acrylic acid polymer by reacting the functional group with an unsaturated group in an unsaturated group-containing compound described later can be exemplified.

[0128] As the functional group-containing monomer, for example, a hydroxyl group-containing monomer, a carboxyl group-containing monomer, an amino group-containing monomer, an epoxy group-containing monomer, and the like can be exemplified.

[0129] The acrylic acid polymer can further have a structural unit derived from another monomer in addition to the structural unit derived from the alkyl (meth)acrylate and the structural unit derived from the functional group-containing monomer.

[0130] The other monomer is not particularly limited as long as it is capable of being copolymerized with the alkyl (meth)acrylate or the like.

[0131] As the other monomer, for example, styrene, α-methylstyrene, vinyltoluene, vinyl formate, vinyl acetate, acrylonitrile, acrylamide, and the like can be exemplified.

[0132] In the adhesive composition (I-1) to (I-3), the acrylic acid resin can have only one kind of structural unit, or two or more kinds of structural units, and in the case of two or more kinds of structural units, the combination and the ratio thereof can be arbitrarily selected.

[0133] In the acrylic acid polymer, the content of the structural unit derived from the functional group-containing monomer is preferably 1 to 35% by mass relative to the total amount of the structural units.

[0134] The adhesive resin (I-1a) contained in the adhesive composition (I-1) can be only one kind, or two or more kinds, and in the case of two or more kinds, the combination and the ratio thereof can be arbitrarily selected.

[0135] In the adhesive composition (I-1), the content of the adhesive resin (I-1a) is preferably 5 to 99% by mass relative to the total mass of the adhesive composition (I-1).

[0136] [Adhesive resin (I-2a)]

[0137] The adhesive resin (I-2a) in the adhesive compositions (I-2) and (I-3) can be obtained, for example, by reacting the functional group in the adhesive resin (I-la) with an unsaturated group-containing compound having an energy ray-polymerizable unsaturated group.

[0138] The unsaturated group-containing compound further has, in addition to the energy ray-polymerizable unsaturated group, a group capable of bonding to the adhesive resin (I-la) by reaction with the functional group in the adhesive resin (I-la).

[0139] As the energy ray-polymerizable unsaturated group, for example, (meth)acryloyl group, vinyl (ethenyl) group, allyl (2-propenyl) group, and the like can be exemplified, with (meth)acryloyl group being preferred.

[0140] As the group capable of bonding to the functional group in the adhesive resin (I-la), for example, isocyanate group and glycidyl group capable of bonding to hydroxyl group or amino group, and hydroxyl group and amino group capable of bonding to carboxyl group or epoxy group, and the like can be exemplified.

[0141] As the unsaturated group-containing compound, for example, (meth)acryloyloxyethyl isocyanate, (meth)acryloyl isocyanate, (meth)acrylic acid glycidyl ester, and the like can be exemplified.

[0142] The adhesive resin (I-2a) contained in the adhesive composition (I-2) or (I-3) can be only one, or two or more, and in the case of two or more, the combination and ratio thereof can be arbitrarily selected.

[0143] In the adhesive composition (I-2) or (I-3), the content of the adhesive resin (I-2a) is preferably 5 to 99% by mass relative to the total mass of the adhesive composition (I-2) or (I-3).

[0144] [Energy ray-curable compound]

[0145] As the energy ray-curable compound in the adhesive compositions (I-l) and (I-3), a monomer or oligomer having an energy ray-polymerizable unsaturated group and capable of being cured by irradiation of energy rays can be exemplified.

[0146] In the energy ray-curable compound, as the monomer, for example, there can be mentioned a polyvalent (meth)acrylate such as trimethylolpropane tri(meth)acrylate, pentaerythritol (meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol (meth)acrylate, etc.; urethane (meth)acrylate; polyester (meth)acrylate; polyether (meth)acrylate; epoxy (meth)acrylate, etc.

[0147] In the energy ray-curable compound, as the oligomer, for example, there can be mentioned an oligomer obtained by polymerizing the above exemplified monomer, etc.

[0148] The energy ray-curable compound contained in the adhesive composition (I-1) or (I-3) can be only one, or two or more, and in the case of two or more, the combination and ratio thereof can be arbitrarily selected.

[0149] In the adhesive composition (I-1), the content of the energy ray-curable compound is preferably 1 to 95% by mass relative to the total mass of the adhesive composition (I-1).

[0150] In the adhesive composition (I-3), the content of the energy ray-curable compound is preferably 0.01 to 300 parts by mass relative to 100 parts by mass of the content of the adhesive resin (I-2a).

[0151] [Crosslinking agent]

[0152] When the acrylic acid polymer further having a structural unit from a functional group-containing monomer in addition to a structural unit from an alkyl (meth)acrylate is used as the adhesive resin (I-1a), the adhesive composition (I-1) preferably further contains a crosslinking agent.

[0153] Further, for example, when the acrylic acid polymer having the same structural unit as the structural unit from the functional group-containing monomer in the adhesive resin (I-1a) is used as the adhesive resin (I-2a), the adhesive composition (I-2) or (I-3) can further contain a crosslinking agent.

[0154] The crosslinking agent, for example, reacts with the functional group to crosslink the adhesive resin (I-1a) to each other or the adhesive resin (I-2a) to each other.

[0155] As the crosslinking agent, for example, isocyanate-based crosslinking agents (crosslinking agents having an isocyanate group) such as toluene diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, adducts of these diisocyanates, and the like; epoxy-based crosslinking agents (crosslinking agents having a glycidyl group) such as ethylene glycol glycidyl ether and the like; aziridine-based crosslinking agents (crosslinking agents having an aziridine group) such as hexa[1-(2-methyl)-aziridinyl]triphosphatriazine and the like; metal chelate-based crosslinking agents (crosslinking agents having a metal chelate structure) such as aluminum chelates and the like; isocyanurate-based crosslinking agents (crosslinking agents having an isocyanurate skeleton) and the like can be exemplified.

[0156] The crosslinking agent contained in the adhesive compositions (I-1) to (I-3) can be only one, or two or more, and in the case of two or more, the combination and ratio thereof can be arbitrarily selected.

[0157] In the adhesive composition (I-1), the content of the crosslinking agent is preferably 0.01 to 50 parts by mass, for example, any one of 0.01 to 35 parts by mass, 0.01 to 20 parts by mass, and the like, relative to 100 parts by mass of the content of the adhesive resin (I-1a).

[0158] In the adhesive composition (I-2) or (I-3), the content of the crosslinking agent is preferably 0.01 to 50 parts by mass, for example, any one of 0.01 to 35 parts by mass, 0.01 to 20 parts by mass, 0.01 to 10 parts by mass, and the like, relative to 100 parts by mass of the content of the adhesive resin (I-2a).

[0159] [Photopolymerization initiator]

[0160] The adhesive compositions (I-1) to (I-3) can further contain a photopolymerization initiator. Even if the adhesive compositions (I-1) to (I-3) containing a photopolymerization initiator are irradiated with energy rays of lower energy such as ultraviolet rays, the curing reaction sufficiently proceeds.

[0161] As the photopolymerization initiator, for example, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzoin benzoate, benzoin benzoate methyl ester, benzoin dimethyl ketal, and the like can be exemplified. As the photopolymerization initiator, for example, acetophenone, 2-hydroxy-2-methyl-l-phenyl-propane-l-one, 2,2-dimethoxy-l,2-diphenylethane-l-one, 2-hydroxy-l-(4-(4-(2-hydroxy-2-methylpropionyl)benzyl)phenyl)-2-methylpropane-l-one, and the like can be exemplified. As the photopolymerization initiator, for example, phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, and the like can be exemplified. As the photopolymerization initiator, for example, benzyl phenyl sulfide, tetramethylthiuram monosulfide, and the like can be exemplified. As the photopolymerization initiator, for example, l-hydroxycyclohexyl phenyl ketone, and the like can be exemplified. As the photopolymerization initiator, for example, azobisisobutyronitrile, and the like can be exemplified. As the photopolymerization initiator, for example, titanocene dichloride, and the like can be exemplified. As the photopolymerization initiator, for example, thioxanthone, and the like can be exemplified. As the photopolymerization initiator, for example, peroxide compounds, diketone compounds, benzil, benzil dimethyl acetal, benzophenone, 2,4-diethylthioxanthone, 1,2-diphenylmethane, 2-hydroxy-2-methyl-l-[4-(l-methylethenyl)phenyl]propanone, 1-chloroanthraquinone, 2-chloroanthraquinone, and the like can be exemplified.

[0162] Further, as the photopolymerization initiator, for example, a photosensitizer such as amine, and the like can be used.

[0163] The photopolymerization initiator contained in the adhesive composition (I-1) to (I-3) can be only one, or two or more, and in the case of two or more, the combination and the ratio thereof can be arbitrarily selected.

[0164] In the adhesive composition (I-1), the content of the photopolymerization initiator is preferably 0.01 to 20 parts by mass, relative to 100 parts by mass of the content of the energy ray-curable compound.

[0165] In the adhesive composition (I-2), the content of the photopolymerization initiator is preferably 0.01 to 20 parts by mass, relative to 100 parts by mass of the content of the adhesive resin (I-2a), and for example, can be any one range of 0.01 to 10 parts by mass and 0.01 to 5 parts by mass.

[0166] In the adhesive composition (I-3), the content of the photopolymerization initiator is preferably 0.01 to 20 parts by mass, relative to 100 parts by mass of the total content of the adhesive resin (I-2a) and the energy ray-curable compound.

[0167] The gel fraction of the adhesive composition (I-1) to (I-3) can be adjusted by the molecular weight of the polymer as a material of the adhesive composition, the amount of the functional group as a crosslinking starting point, the blending amount of the crosslinking agent, and the like. For example, the gel fraction of the adhesive composition can be increased by increasing the blending amount of the crosslinking agent.

[0168] [Other additives]

[0169] The adhesive compositions (I-1) to (I-3) can contain other additives other than any of the above-mentioned components, within a range not impairing the effects of the present application.

[0170] As the other additives, for example, known additives such as antistatic agents, antioxidants, softening agents (plasticizers), filling materials, rust-preventive agents, coloring agents (pigments, dyes), sensitizers, tackifiers, reaction retardants, crosslinking accelerators (catalysts), and the like can be exemplified.

[0171] In addition, the reaction retardant refers to an additive that suppresses non-purpose crosslinking reactions in the adhesive compositions (I-1) to (I-3) in storage, for example, by mixing a catalyst in the adhesive compositions (I-1) to (I-3). As the reaction retardant, for example, a reaction retardant that forms a chelate complex using a chelate compound against a catalyst can be exemplified, and more specifically, a reaction retardant having two or more carbonyl groups (-C(=O)-) in one molecule can be exemplified.

[0172] The other additives contained in the adhesive compositions (I-1) to (I-3) can be only one, or two or more, and when two or more, the combination and ratio thereof can be arbitrarily selected.

[0173] The content of the other additives of the adhesive compositions (I-1) to (I-3) is not particularly limited, and is appropriately selected depending on the kind thereof.

[0174] [Solvent]

[0175] The adhesive compositions (I-1) to (I-3) can contain a solvent. By containing a solvent in the adhesive compositions (I-1) to (I-3), the coating adaptability to the coating target surface is improved.

[0176] In addition, in the present specification, the concept of "solvent" includes not only a solvent that dissolves an object component, but also a dispersion medium that disperses an object component, unless otherwise specified.

[0177] The solvent is preferably an organic solvent, and as the organic solvent, for example, ketones such as methyl ethyl ketone and acetone; esters (carboxylic acid esters) such as ethyl acetate; ethers such as tetrahydrofuran and dioxane; aliphatic hydrocarbons such as cyclohexane and n-hexane; aromatic hydrocarbons such as toluene and xylene; alcohols such as 1-propanol and 2-propanol, and the like are exemplified.

[0178] The solvent contained in the adhesive composition (I-1) to (I-3) can be only one or two or more, and the combination and ratio thereof can be arbitrarily selected.

[0179] The content of the solvent in the adhesive composition (I-1) to (I-3) is not particularly limited, and can be appropriately adjusted.

[0180] Method for producing an adhesive composition

[0181] The adhesive composition (I-1) to (I-3) and the like can be obtained by blending the adhesive and each component according to the desired components other than the adhesive for constituting the adhesive composition.

[0182] The order of addition of each component at the time of blending is not particularly limited, and two or more components can be simultaneously added.

[0183] The method of mixing each component at the time of blending is not particularly limited, and can be appropriately selected from the following known methods: a method in which a stirrer or a stirring blade or the like is rotated to perform mixing; a method in which a mixer is used to perform mixing; a method in which ultrasonic waves are applied to perform mixing; and the like.

[0184] The temperature and the time at the time of adding and mixing each component are not particularly limited as long as each blended component is not deteriorated, and can be appropriately adjusted, but the temperature is preferably 15 to 30°C.

[0185] Film for protective film formation

[0186] For example, as described later, a film for protective film formation can be constituted by laminating a film for protective film formation and a support sheet having an adhesive layer.

[0187] The film for protective film formation forms a protective film for protecting an arbitrary position of a workpiece and a workpiece processed product. When the workpiece is a semiconductor wafer, by using the film for protective film formation of the present embodiment, a protective film can be formed on a surface (in the present specification, sometimes referred to as "back surface") of a semiconductor wafer and a semiconductor chip which is opposite to a circuit formation surface. In the present specification, the workpiece processed product having the protective film described above can be referred to as a "workpiece processed product with a protective film", and the semiconductor chip having the protective film on the back surface can be referred to as a "semiconductor chip with a protective film".

[0188] The film for protective film formation is soft, and can be easily attached to an attachment target object such as a workpiece and a workpiece processed product.

[0189] The protective film-forming film can function as a protective film by being cured, or can function as a protective film in an uncured state. The protective film-forming film that functions as a protective film in an uncured state can be regarded as having formed a protective film at the stage of being attached to the target position of the workpiece, for example.

[0190] As described above, the protective film-forming film can be curable or non-curable.

[0191] The curable protective film-forming film can be either thermosetting or energy ray-curable, or can have both thermosetting and energy ray-curable properties.

[0192] In the present specification, "non-curable" means a property of not being cured even by any means such as heating or irradiation of energy rays.

[0193] When the protective film-forming film is thermally cured to form a protective film, since it is sufficiently cured by heating, a protective film having high protective performance can be formed even if the thickness of the protective film-forming film is thick. Furthermore, by using a general heating means such as a heating oven, a plurality of protective film-forming films can be heated and thermally cured at once.

[0194] When the protective film-forming film is cured by irradiation of energy rays to form a protective film, unlike when it is thermally cured, the protective film-forming composite sheet does not need to have heat resistance, and a wide range of protective film-forming composite sheets can be constituted. Furthermore, it can be cured in a short time by irradiation of energy rays.

[0195] When the protective film-forming film is used as a protective film without being cured, since the curing process can be omitted, a workpiece processed product with a protective film can be manufactured in a simplified process.

[0196] Regardless of whether the protective film-forming film is curable or non-curable, the protective film-forming film can be composed of one layer (single layer), or can be composed of a plurality of layers of two or more layers, and when the protective film-forming film is curable, regardless of whether it is thermosetting or energy ray-curable, the protective film-forming film can be composed of one layer (single layer), or can be composed of a plurality of layers of two or more layers. When the protective film-forming film is composed of a plurality of layers, the plurality of layers can be the same as each other, or can be different from each other, and the combination of the plurality of layers is not particularly limited.

[0197] The thickness of the protective film forming film is preferably 1 to 100 μm, more preferably 3 to 80 μm, and particularly preferably 5 to 60 μm, for example, any one of 5 to 40 μm and 5 to 20 μm, regardless of whether the protective film forming film is curable or non-curable, and the thickness of the protective film forming film is preferably 1 to 100 μm, more preferably 3 to 80 μm, and particularly preferably 5 to 60 μm, for example, any one of 5 to 40 μm and 5 to 20 μm, regardless of whether the protective film forming film is thermosetting or energy ray-curable. By making the thickness of the protective film forming film be the lower limit value or more, a protective film having higher protective performance can be formed. By making the thickness of the protective film forming film be the upper limit value or less, an excessively thick thickness can be avoided.

[0198] In the formula, "the thickness of the protective film forming film" refers to the thickness of the entire protective film forming film, and for example, the thickness of a protective film forming film composed of a plurality of layers refers to the total thickness of all layers constituting the protective film forming film.

[0199] In the protective film forming composite sheet of the first embodiment, the glass transition temperature (Tg) of the protective film forming film is preferably 3°C or higher, more preferably 5°C or higher, and further preferably 15°C or higher.

[0200] The glass transition temperature of the protective film forming film is, for example, 10°C or higher, 20°C or higher. By making the glass transition temperature of the protective film forming film be the lower limit value or more, the movement of components between the energy ray-curable adhesive layer before energy ray curing and the protective film forming film before energy ray curing can be suppressed, peeling between the semiconductor chip and the protective film does not occur when the semiconductor chip with the protective film is picked up from the support sheet, and the effect of peeling the semiconductor chip with the protective film from the support sheet is further improved.

[0201] In the protective film forming composite sheet of the second embodiment, the glass transition temperature (Tg) of the protective film forming film is 3°C or higher, preferably 5°C or higher, more preferably 15°C or higher, and further preferably 20°C or higher, for example, 10°C or higher. By making the glass transition temperature of the protective film forming film be the lower limit value or more, even if the gel fraction of the adhesive layer before energy ray curing is 20% or more and less than 80%, the movement of components between the energy ray-curable adhesive layer before energy ray curing and the protective film forming film before energy ray curing can be suppressed, peeling between the semiconductor chip and the protective film does not occur when the semiconductor chip with the protective film is picked up from the support sheet, and the semiconductor chip with the protective film can be peeled from the support sheet.

[0202] In the protective film forming composite sheet of the first embodiment and the protective film forming composite sheet of the second embodiment, the protective film forming film preferably has a loss modulus E" of 3 MPa or more, more preferably 5 MPa or more, for example, 10 MPa or more, 15 MPa or more, 20 MPa or more, 25 MPa or more, 30 MPa or more, 40 MPa or more, 50 MPa or more, or the like at 23°C.

[0203] The upper limit of the loss modulus E" of the protective film forming film at 23°C is not particularly limited. For example, a protective film forming film having a loss modulus E" of 100 MPa or less can be easily manufactured.

[0204] The method for measuring the glass transition temperature (Tg) and the loss modulus E" of the protective film forming film at 23°C can be measured using a publicly known method. Specifically, the measurement can be performed by the following method.

[0205] The sample was laminated in a manner such that the thickness was about 200 μm, and a laminate was obtained. The laminate was processed to have a size of 4 mm in width and 30 mm in length (distance between the clamps), and a test piece was prepared. Using an automatic dynamic viscoelasticity tester (manufactured by ORIENTEC Co., Ltd., product name "Rheovibron DDV-0.1 FP"), the tensile loss modulus E" of the test piece at 23°C was measured at a measurement frequency of 1 Hz, and the peak temperature of tan δ at this time was taken as the glass transition temperature (Tg).

[0206]

[0207] The protective film forming film can be formed using a protective film forming composition containing the constituent materials thereof. For example, the protective film forming film can be formed by applying the protective film forming composition on the surface on which the film is to be formed, and drying as necessary. The content ratio of the components that do not vaporize at ordinary temperature to each other in the protective film forming composition is usually the same as the content ratio of the components to each other in the protective film forming film.

[0208] The thermosetting protective film forming film can be formed using a thermosetting protective film forming composition, the energy ray-curable protective film forming film can be formed using an energy ray-curable protective film forming composition, and the non-curable protective film forming film can be formed using a non-curable protective film forming composition. In addition, in the present specification, when the protective film forming film has both thermosetting and energy ray-curable properties, and for the formation of the protective film, when the contribution of the thermosetting of the protective film forming film is greater than the contribution of the energy ray-curing, the protective film forming film is regarded as a thermosetting film. Conversely, for the formation of the protective film, when the contribution of the energy ray-curing of the protective film forming film is greater than the contribution of the thermosetting, the protective film forming film is regarded as an energy ray-curable film. ​

[0209] The coating of the protective film-forming composition can be performed, for example, by the same method as the coating adhesive composition described above.

[0210] The drying conditions of the protective film-forming composition are not particularly limited regardless of which one of the curable and non-curable protective film-forming film is used, and when the protective film-forming film is curable, the drying conditions of the protective film-forming composition are also not particularly limited regardless of which one of the thermosetting and energy ray-curable is used. However, when the protective film-forming composition contains a solvent described later, heating drying is preferably performed. Also, the protective film-forming composition containing a solvent is, for example, preferably subjected to heating drying at 70 to 130°C for 10 seconds to 5 minutes. However, the thermosetting protective film-forming composition is preferably subjected to heating drying in such a manner that the thermosetting protective film-forming composition itself is not thermally cured and the thermosetting protective film-forming film formed from the composition is not thermally cured.

[0211] Hereinafter, the thermosetting protective film-forming film, the energy ray-curable protective film-forming film, and the non-curable protective film-forming film will be described in order.

[0212] ■Thermosetting protective film-forming film

[0213] The curing conditions when the thermosetting protective film-forming film is attached to the target position of the workpiece and is thermally cured to form a protective film are not particularly limited as long as the protective film is cured to a degree that is sufficient to exhibit its function, and appropriate selection is possible depending on the type of the thermosetting protective film-forming film.

[0214] For example, the heating temperature at the time of thermal curing of the thermosetting protective film-forming film is preferably 100 to 200°C, more preferably 110 to 180°C, and particularly preferably 120 to 170°C. Also, the heating time at the time of thermal curing is preferably 0.5 to 5 hours, more preferably 0.5 to 3 hours, and particularly preferably 1 to 2 hours.

[0215] 100 to 200°C, more preferably 110 to 180°C, and particularly preferably 120 to 170°C. Also, the heating time at the time of thermal curing is preferably 0.5 to 5 hours, more preferably 0.5 to 3 hours, and particularly preferably 1 to 2 hours.

[0216] As a preferred thermosetting protective film-forming film, for example, a thermosetting protective film-forming film containing a polymer component (A) and a thermosetting component (B) can be cited. The polymer component (A) is a component formed by polymerization of a polymerizable compound. Also, the thermosetting component (B) is a component capable of undergoing a curing (polymerization) reaction with heat as a reaction trigger. In addition, the polymerization reaction in the present specification also includes a polycondensation reaction.

[0217] <Thermosetting protective film-forming composition (III-1)>

[0218] As the preferred thermosetting protective film-forming composition, for example, a thermosetting protective film-forming composition (III-1) (in this specification, sometimes abbreviated as "composition (III-1)") containing the polymer component (A) and the thermosetting component (B) and the like can be exemplified.

[0219] [Polymer component (A)]

[0220] The polymer component (A) is a component for imparting film-forming properties and flexibility and the like to the thermosetting protective film-forming film.

[0221] The polymer component (A) contained in the composition (III-1) and the thermosetting protective film-forming film can be only one, or two or more, and in the case of two or more, the combination and the ratio thereof can be arbitrarily selected.

[0222] As the polymer component (A), for example, an acrylic resin, a polyester, a urethane resin, an acrylic urethane resin, a silicone resin, a rubber-based resin, a phenoxy resin, a thermoplastic polyimide and the like can be exemplified, and an acrylic resin is preferred.

[0223] As the acrylic resin in the polymer component (A), a publicly known acrylic polymer can be exemplified.

[0224] The weight average molecular weight (Mw) of the acrylic resin is preferably 10,000 to 2,000,000, and more preferably 100,000 to 1,500,000. By making the weight average molecular weight of the acrylic resin be the lower limit value or more, the shape stability (time-dependent stability during storage) of the thermosetting protective film-forming film is improved. Further, by making the weight average molecular weight of the acrylic resin be the upper limit value or less, the thermosetting protective film-forming film becomes easy to follow the uneven surface of the adherend, and generation of voids and the like between the adherend and the thermosetting protective film-forming film can be further suppressed.

[0225] In addition, in this specification, unless otherwise specified, the "weight average molecular weight" means a polystyrene conversion value measured by a gel permeation chromatography (GPC) method.

[0226] The glass transition temperature (Tg) of the acrylic resin is preferably 3°C or higher and 70°C or lower, and more preferably 3°C or higher and 50°C or lower. By setting the Tg of the acrylic resin to be the lower limit value or higher, the components are inhibited from moving between the energy ray-curable adhesive layer and the protective film-forming film before the energy ray curing, and peeling between the semiconductor chip and the protective film does not occur when the semiconductor chip with the protective film is picked up from the support sheet, and the effect of peeling the semiconductor chip with the protective film from the support sheet is further improved. In addition, by setting the Tg of the acrylic resin to be the upper limit value or lower, the adhesion of the thermosetting protective film-forming film and the cured product thereof to the adherend is improved.

[0227] As the acrylic resin, for example, one or two or more kinds of (meth)acrylate polymers; a copolymer of two or more kinds of monomers selected from the group consisting of (meth)acrylic acid, itaconic acid, ethyl acetate, acrylonitrile, styrene, and N-hydroxymethyl acrylamide, and the like can be exemplified.

[0228] As the (meth)acrylate constituting the acrylic resin, for example, methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, sec-butyl (meth)acrylate, t-butyl (meth)acrylate, amyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isooctyl (meth)acrylate, n-octyl (meth)acrylate, n-nonyl (meth)acrylate, isononyl (meth)acrylate, decyl (meth)acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate (lauric (meth)acrylate), tridecyl (meth)acrylate, myristic (meth)acrylate ((meth)acrylate), pentadecyl (meth)acrylate, palmitic (meth)acrylate ((meth)acrylate), heptadecyl (meth)acrylate, stearyl (meth)acrylate ((meth)acrylate), and the like in which the alkyl group constituting the alkyl ester is a chain structure having a carbon number of 1 to 18;

[0229] isobornyl (meth)acrylate, dicyclopentyl (meth)acrylate, and the like in which the cycloalkyl group is a cyclic structure having a carbon number of 5 to 10;

[0230] benzyl (meth)acrylate, and the like in which the aralkyl group is a structure in which an aromatic ring and an alkyl group are bonded to each other;

[0231] dicyclopentenyl (meth)acrylate, and the like in which the cycloalkenyl group is a cyclic structure having a carbon number of 5 to 10;

[0232] dicyclopentenyl (meth)acrylate, and the like in which the cycloalkenyl group is a cyclic structure having a carbon number of 5 to 10;

[0233] (meth)acrylimide;

[0234] (Meth)acrylates containing glycidyl groups, such as glycidyl acrylate;

[0235] Hydroxymethyl methacrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 3-hydroxypropyl methacrylate, 2-hydroxybutyl methacrylate, 3-hydroxybutyl methacrylate, 4-hydroxybutyl methacrylate, and other hydroxyl-containing methacrylates;

[0236] (Meth)acrylates such as N-methylaminoethyl methacrylate and other (meth)acrylates containing substituted amino groups. Here, "substituted amino group" refers to a group in which one or two hydrogen atoms of the amino group are replaced by a group other than a hydrogen atom.

[0237] Acrylic resins can be, for example, resins that, in addition to the (meth)acrylates mentioned above, also copolymerize one or more monomers selected from (meth)acrylic acid, itaconic acid, vinyl acetate, acrylonitrile, styrene, and N-hydroxymethylacrylamide.

[0238] The monomers that make up acrylic resin can be just one type or two or more types. When there are two or more types, their combination and ratio can be arbitrarily selected.

[0239] Acrylic resins may possess functional groups such as vinyl, (meth)acryloyl, amino, hydroxyl, carboxyl, and isocyanate groups, which enable them to bond with other compounds. These functional groups of the acrylic resin can be bonded to other compounds via a crosslinking agent (F) described later, or they can be directly bonded to other compounds without the crosslinking agent (F). By bonding the acrylic resin to other compounds through these functional groups, there is a tendency to improve the reliability of the package obtained using a composite sheet for forming a protective film.

[0240] In this invention, as polymer component (A), a thermoplastic resin other than acrylic resin (hereinafter sometimes simply abbreviated as "thermoplastic resin") may be used alone instead of acrylic resin, or both acrylic resin and a thermoplastic resin other than acrylic resin may be used simultaneously. By using the thermoplastic resin, the peelability of the protective film from the support sheet is improved, or the thermosetting protective film forming film becomes easier to follow the uneven surface of the adhered object, and the generation of gaps between the adhered object and the thermosetting protective film forming film can be further suppressed.

[0241] The weight-average molecular weight of the thermoplastic resin is preferably 1,000 to 100,000, more preferably 3,000 to 80,000.

[0242] The glass transition temperature (Tg) of the thermoplastic resin is preferably 3°C or higher and 150°C or lower, more preferably 3°C or higher and 120°C or lower.

[0243] As the thermoplastic resin, for example, polyester, polyurethane, phenoxy resin, polybutene, polybutadiene, polystyrene, and the like can be exemplified.

[0244] The thermoplastic resin contained in the composition (III-1) and the thermosetting protective film-forming film can be only one, or two or more, and in the case of two or more, the combination and ratio thereof can be arbitrarily selected.

[0245] In the composition (III-1), the proportion of the content of the polymer component (A) with respect to the total content of all components except for the solvent (i.e., the proportion of the content of the polymer component (A) in the thermosetting protective film-forming film with respect to the total mass of the thermosetting protective film-forming film) is preferably 10 to 85% by mass, more preferably 15 to 70% by mass, further preferably 20 to 60% by mass, and for example, can be any one of 20 to 45% by mass and 20 to 35% by mass, or any one of 35 to 60% by mass and 45 to 60% by mass.

[0246] The polymer component (A) sometimes also belongs to the thermosetting component (B). In the present application, when the composition (III-1) contains the above component which belongs to both the polymer component (A) and the thermosetting component (B), it is regarded as containing the polymer component (A) and the thermosetting component (B).

[0247] [Thermosetting Component (B)]

[0248] The thermosetting component (B) is a component for curing the thermosetting protective film-forming film.

[0249] The thermosetting component (B) contained in the composition (III-1) and the thermosetting protective film-forming film can be only one, or two or more, and in the case of two or more, the combination and ratio thereof can be arbitrarily selected.

[0250] As the thermosetting component (B), for example, an epoxy-based thermosetting resin, a polyimide-based resin, an unsaturated polyester resin, and the like can be exemplified, and an epoxy-based thermosetting resin is preferred.

[0251] (Epoxy-Based Thermosetting Resin)

[0252] The epoxy-based thermosetting resin is formed of an epoxy resin (B1) and a thermosetting agent (B2).

[0253] The epoxy thermosetting resin contained in the composition (III-1) and the thermosetting protective film forming film can be only one type or two or more types. When there are two or more types, their combination and ratio can be arbitrarily selected.

[0254] ·Epoxy resin (B1)

[0255] As for epoxy resin (B1), well-known epoxy resins can be listed, such as multifunctional epoxy resins, biphenyl compounds, bisphenol A diglycidyl ether and its hydrides, o-cresol phenolic varnish epoxy resin, dicyclopentadiene type epoxy resin, biphenyl type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenylene skeleton type epoxy resin, and other epoxy compounds with more than one function.

[0256] As the epoxy resin (B1), an epoxy resin having unsaturated hydrocarbon groups can be used. The compatibility of epoxy resins with unsaturated hydrocarbon groups with acrylic resins is higher than that of epoxy resins without unsaturated hydrocarbon groups with acrylic resins. Therefore, by using epoxy resins with unsaturated hydrocarbon groups, the reliability of workpieces with a protective film obtained using a protective film forming composite sheet is improved.

[0257] As epoxy resins having unsaturated hydrocarbon groups, examples include compounds in which a portion of the epoxy groups of multifunctional epoxy resins are converted into groups having unsaturated hydrocarbon groups. These compounds can be obtained, for example, by adding an addition reaction of (meth)acrylic acid or a derivative thereof to the epoxy groups.

[0258] Furthermore, examples of epoxy resins containing unsaturated hydrocarbon groups include compounds formed by direct bonding of unsaturated hydrocarbon groups to aromatic rings that constitute epoxy resins.

[0259] Unsaturated hydrocarbon groups are unsaturated groups that can polymerize. Specific examples include methine (vinyl), 2-propenyl (allyl), (meth)acryloyl, (meth)acrylamido, etc., with acryloyl being preferred.

[0260] The number average molecular weight of epoxy resin (B1) is not particularly limited, but from the perspective of curability of the film for forming thermosetting protective film and the strength and heat resistance of the protective film as its cured product, it is preferably 300 to 30,000, more preferably 300 to 10,000, and particularly preferably 300 to 3,000.

[0261] The epoxy equivalent of the epoxy resin (B1) is preferably 100 to 1000 g / eq, more preferably 150 to 950 g / eq.

[0262] Epoxy resin (B1) can be used alone or in combination with two or more. When two or more are used, their combination and ratio can be chosen arbitrarily.

[0263] • Heat curing agent (B2)

[0264] The heat curing agent (B2) functions as a curing agent for the epoxy resin (Bl).

[0265] As the heat curing agent (B2), for example, a compound having two or more functional groups capable of reacting with an epoxy group in one molecule can be exemplified. As the functional group, for example, a phenolic hydroxyl group, an alcoholic hydroxyl group, an amino group, a carboxyl group, a group obtained by anhydridizing an acid group, and the like can be exemplified, with a phenolic hydroxyl group, an amino group, or a group obtained by anhydridizing an acid group being preferred, and a phenolic hydroxyl group or an amino group being more preferred.

[0266] In the heat curing agent (B2), as a phenolic curing agent having a phenolic hydroxyl group, for example, a polyfunctional phenol resin, a biphenol, a novolak-type phenol resin, a dicyclopentadiene-type phenol resin, an aralkyl-type phenol resin, and the like can be exemplified.

[0267] In the heat curing agent (B2), as an amine curing agent having an amino group, for example, a dicyandiamide and the like can be exemplified.

[0268] The heat curing agent (B2) can have an unsaturated hydrocarbon group.

[0269] As the heat curing agent (B2) having an unsaturated hydrocarbon group, for example, a compound in which a part of the hydroxyl groups of a phenol resin is substituted with a group having an unsaturated hydrocarbon group, a compound in which a group having an unsaturated hydrocarbon group is directly bonded to the aromatic ring of a phenol resin, and the like can be exemplified.

[0270] The unsaturated hydrocarbon group in the heat curing agent (B2) is the same as the unsaturated hydrocarbon group in the above-described epoxy resin having an unsaturated hydrocarbon group.

[0271] When a phenolic curing agent is used as the heat curing agent (B2), from the viewpoint of improving the peelability of the protective film from the support sheet, it is preferred that the heat curing agent (B2) have a high softening point or glass transition temperature.

[0272] In the heat curing agent (B2), the number average molecular weight of the resin component, for example, a polyfunctional phenol resin, a novolak-type phenol resin, a dicyclopentadiene-type phenol resin, an aralkyl-type phenol resin, and the like is preferably 300 to 30,000, more preferably 400 to 10,000, and particularly preferably 500 to 3,000.

[0273] In the heat curing agent (B2), the molecular weight of the non-resin component, for example, a biphenol, a dicyandiamide, and the like is not particularly limited, but is preferably, for example, 60 to 500.

[0274] The heat curing agent (B2) can be used alone or two or more kinds can be used simultaneously, and the combination and ratio thereof can be arbitrarily selected when two or more kinds are used simultaneously.

[0275] In the composition (III-1) and the thermosetting protective film forming film, the content of the thermosetting agent (B2) is preferably 0.1 to 100 parts by mass, more preferably 0.5 to 50 parts by mass, for example, any one of 0.5 to 25 parts by mass, 0.5 to 10 parts by mass, and 0.5 to 5 parts by mass, with respect to 100 parts by mass of the content of the epoxy resin (B1). By making the content of the thermosetting agent (B2) be the above lower limit value or more, it becomes easier to perform the curing of the thermosetting protective film forming film. By making the content of the thermosetting agent (B2) be the above upper limit value or less, the moisture absorption rate of the thermosetting protective film forming film decreases, and the reliability of the package obtained using the protective film forming composite sheet is further improved.

[0276] In the composition (III-1) and the thermosetting protective film forming film, the content of the thermosetting component (B) (for example, the total content of the epoxy resin (B1) and the thermosetting agent (B2)) is preferably 5 to 120 parts by mass, more preferably 5 to 80 parts by mass, for example, any one of 5 to 40 parts by mass, 5 to 20 parts by mass, and 5 to 10 parts by mass, and also any one of 40 to 80 parts by mass, 50 to 75 parts by mass, and 60 to 75 parts by mass, with respect to 100 parts by mass of the content of the polymer component (A). By making the content of the thermosetting component (B) be the above range, for example, the adhesion of the cured product of the protective film forming film to the support sheet is suppressed, and the peelability of the support sheet is improved.

[0277] [Curing accelerator (C)]

[0278] The composition (III-1) and the thermosetting protective film forming film can contain a curing accelerator (C). The curing accelerator (C) is a component for adjusting the curing speed of the composition (III-1).

[0279] As the preferred curing accelerator (C), for example, tertiary amines such as triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, tris(dimethylaminomethyl)phenol, and the like; imidazoles (imidazoles in which one or more hydrogen atoms are replaced with a group other than a hydrogen atom) such as 2-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, and the like; organophosphines (phosphines in which one or more hydrogen atoms are replaced with an organic group) such as tributylphosphine, diphenylphosphine, triphenylphosphine, and the like; tetraphenylborate salts such as tetraphenylphosphonium tetraphenylborate, triphenylphosphine tetraphenylborate, and the like, and the like can be exemplified.

[0280] The curing accelerator (C) contained in the composition (III-1) and the thermosetting protective film forming film can be only one or two or more. When two or more, the combination and ratio thereof can be arbitrarily selected.

[0281] When the curing accelerator (C) is used, in the composition (III-1) and the thermosetting protective film forming film, the content of the curing accelerator (C) is preferably 0.01 to 10 parts by mass, more preferably 0.1 to 7 parts by mass, relative to 100 parts by mass of the content of the thermosetting component (B). By making the content of the curing accelerator (C) be the lower limit value or more, the effect of using the curing accelerator (C) can be more significantly obtained. By making the content of the curing accelerator (C) be the upper limit value or less, for example, the effect of suppressing the migration of the curing accelerator (C) having high polarity to the adhesive interface side with the adherend in the thermosetting protective film forming film under high temperature and high humidity conditions and causing segregation is increased. As a result, the reliability of the workpiece processed product with the protective film obtained using the protective film forming composite sheet is further improved.

[0282] [Filler (D)]

[0283] The composition (III-1) and the thermosetting protective film forming film can contain a filler (D). By making the thermosetting protective film forming film contain the filler (D), it becomes easy to adjust the thermal expansion coefficient of the thermosetting protective film forming film and the cured product thereof, that is, the protective film, and by optimizing the thermal expansion coefficient with respect to the object to be formed into the protective film, the reliability of the workpiece processed product with the protective film obtained using the protective film forming composite sheet is further improved. In addition, by making the thermosetting protective film forming film contain the filler (D), it is also possible to reduce the moisture absorption rate of the protective film or improve the heat dissipation property.

[0284] The filler (D) can be any one of an organic filler and an inorganic filler, and is preferably an inorganic filler.

[0285] As a preferred inorganic filler, for example, powders such as silicon dioxide, aluminum oxide, talc, calcium carbonate, titanium white, red iron oxide, silicon carbide, boron nitride, and the like; beads obtained by spheroidizing these inorganic fillers; surface-modified products of these inorganic fillers; single crystal fibers of these inorganic fillers; glass fibers, and the like can be listed.

[0286] Among them, the inorganic filler is preferably silicon dioxide or aluminum oxide, and more preferably silicon dioxide.

[0287] The filler (D) contained in the composition (III-1) and the thermosetting protective film forming film can be only one or two or more. When two or more, the combination and ratio thereof can be arbitrarily selected.

[0288] In the composition (III-1), the proportion of the content of the filler material (D) with respect to the total content of all components except for the solvent (i.e., the proportion of the content of the filler material (D) in the thermosetting protective film-forming film with respect to the total mass of the thermosetting protective film-forming film) is preferably 50% by mass or more, more preferably 55% by mass or more. The upper limit of the proportion of the content of the filler material (D) is preferably 80% by mass or less, preferably 70% by mass or less, and for example, can be any one of 50% by mass or more and 80% by mass or less, and 55% by mass or more and 80% by mass or less, or can be any one of 50% by mass or more and 70% by mass or less, and 55% by mass or more and 70% by mass or less. By setting the proportion to the above range, the components can be inhibited from moving between the energy ray-curable adhesive layer and the protective film-forming film before the energy ray curing.

[0289] [Coupling agent (E)]

[0290] The composition (III-1) and the thermosetting protective film-forming film can contain a coupling agent (E). By using a coupling agent having a functional group capable of reacting with an inorganic compound or an organic compound as the coupling agent (E), the adhesion and the adhesion property of the thermosetting protective film-forming film to the adherend can be improved. Furthermore, by using the coupling agent (E), the water resistance of the cured product of the thermosetting protective film-forming film is improved without impairing the heat resistance.

[0291] The coupling agent (E) is preferably a compound having a functional group capable of reacting with the functional group possessed by the polymer component (A), the thermosetting component (B), or the like, and more preferably a silane coupling agent.

[0292] As the preferable silane coupling agent, for example, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxy-methyldiethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-(2-aminoethylamino)propyltrimethoxysilane, 3-(2-aminoethylamino)propylmethyldiethoxysilane, 3-(phenylamino)propyltrimethoxysilane, 3-anilinopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, bis(3-triethoxysilylpropyl)tetrasulfide, methyltrimethoxysilane, methyltriethoxysilane, vinyltrimethoxysilane, vinyltriacetoxysilane, imidazole silane, and the like can be exemplified.

[0293] The coupling agent (E) contained in the composition (III-1) and the thermosetting protective film-forming film can be only one or two or more, and the combination and ratio thereof can be arbitrarily selected.

[0294] When the coupling agent (E) is used, in the composition (III-1) and the thermosetting protective film-forming film, the content of the coupling agent (E) is preferably 0.03 to 10 parts by mass, more preferably 0.05 to 5 parts by mass, and particularly preferably 0.1 to 2 parts by mass, relative to 100 parts by mass of the total content of the polymer component (A) and the thermosetting component (B). By making the content of the coupling agent (E) be the lower limit value or more, the effects brought about by the use of the coupling agent (E), such as an improvement in the dispersibility of the filler material (D) in the resin or an improvement in the adhesion of the thermosetting protective film-forming film to the adherend, can be more remarkably obtained. Furthermore, by making the content of the coupling agent (E) be the upper limit value or less, the occurrence of outgassing can be further suppressed.

[0295] [Crosslinking agent (F)]

[0296] When the component having a functional group such as a vinyl group, a (meth)acryloyl group, an amino group, a hydroxyl group, a carboxyl group, an isocyanate group, or the like, which is capable of bonding to other compounds, of the aforementioned acrylic resin or the like is used as the polymer component (A), the composition (III-1) and the thermosetting protective film-forming film can contain a crosslinking agent (F). The crosslinking agent (F) is a component for bonding the functional group in the polymer component (A) to other compounds and performing crosslinking, and by thus performing crosslinking, it is possible to adjust the initial adhesion and cohesion of the thermosetting protective film-forming film.

[0297] As the crosslinking agent (F), for example, an organic polyisocyanate compound, an organic polyvalent imine compound, a metal chelate-based crosslinking agent (a crosslinking agent having a metal chelate structure), an aziridine-based crosslinking agent (a crosslinking agent having an aziridine group), or the like can be exemplified.

[0298] The crosslinking agent (F) contained in the composition (III-1) and the thermosetting protective film-forming film can be only one or two or more, and the combination and ratio thereof can be arbitrarily selected.

[0299] When the crosslinking agent (F) is used, in the composition (III-1), the content of the crosslinking agent (F) is preferably 0.01 to 20 parts by mass, more preferably 0.1 to 10 parts by mass, and particularly preferably 0.5 to 5 parts by mass, relative to 100 parts by mass of the content of the polymer component (A). By making the content of the crosslinking agent (F) be the lower limit value or more, the effects brought about by the use of the crosslinking agent (F) can be more remarkably obtained. Furthermore, by making the content of the crosslinking agent (F) be the upper limit value or less, the excessive use of the crosslinking agent (F) is suppressed.

[0300] [Energy ray-curable resin (G)]

[0301] The composition (III-1) and the thermosetting protective film-forming film can contain an energy ray-curable resin (G). By making the thermosetting protective film-forming film contain the energy ray-curable resin (G), it is possible to change the properties by irradiation of energy rays.

[0302] The energy ray-curable resin (G) is obtained by polymerizing (curing) an energy ray-curable compound.

[0303] As the energy ray-curable compound, for example, a compound having at least one polymerizable double bond in the molecule, preferably an acrylate compound having a (meth)acryloyl group, can be exemplified.

[0304] As the acrylate compound, for example, a (meth)acrylate containing a chain aliphatic skeleton such as trimethylolpropane tri(meth)acrylate, tetramethylolmethane tetra(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol monohydroxy penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate; a (meth)acrylate containing a cyclic aliphatic skeleton such as dicyclopentyl di(meth)acrylate; a polyalkylene glycol (meth)acrylate such as polyethylene glycol di(meth)acrylate; an oligoester (meth)acrylate; a urethane (meth)acrylate oligomer; an epoxy-modified (meth)acrylate; a polyether (meth)acrylate other than the polyalkylene glycol (meth)acrylate; an itaconic acid oligomer, and the like can be exemplified.

[0305] The weight average molecular weight of the energy ray-curable compound is preferably 100 to 30,000, more preferably 300 to 10,000.

[0306] The energy ray-curable compound used for polymerization can be only one, or two or more, and in the case of two or more, the combination and ratio thereof can be arbitrarily selected.

[0307] The energy ray-curable resin (G) contained in the composition (III-1) and the thermosetting protective film-forming film can be only one, or two or more, and in the case of two or more, the combination and ratio thereof can be arbitrarily selected.

[0308] In the case of using the energy ray-curable resin (G), in the composition (III-1), the proportion of the content of the energy ray-curable resin (G) with respect to the total mass of the composition (III-1) is preferably 1 to 95% by mass, more preferably 5 to 90% by mass, particularly preferably 10 to 85% by mass.

[0309] [Photopolymerization initiator (H)]

[0310] When the composition (III-1) and the film for forming a thermosetting protective film contain the energy ray-curable resin (G), in order to efficiently perform the polymerization reaction of the energy ray-curable resin (G), a photopolymerization initiator (H) can be contained.

[0311] As the photopolymerization initiator (H) in the composition (III-1), the same photopolymerization initiators as those which can be contained in the above-mentioned adhesive composition can be exemplified.

[0312] The photopolymerization initiator (H) contained in the composition (III-1) and the film for forming a thermosetting protective film can be only one, or two or more, and when two or more, the combination and ratio thereof can be arbitrarily selected.

[0313] When the photopolymerization initiator (H) is used, in the composition (III-1), the content of the photopolymerization initiator (H) is preferably 0.1 to 20 parts by mass, more preferably 1 to 10 parts by mass, and particularly preferably 2 to 5 parts by mass, relative to 100 parts by mass of the content of the energy ray-curable resin (G).

[0314] [Coloring agent (I)]

[0315] The composition (III-1) and the film for forming a thermosetting protective film preferably contain the coloring agent (I). By using the coloring agent (I), it is possible to more easily produce a protective film-forming film having a transmittance of 60% or less to light (266 nm).

[0316] As the coloring agent (I), well-known coloring agents such as inorganic pigments, organic pigments, and organic dyes can be exemplified.

[0317] As the organic pigments and organic dyes, for example, aminium dyes, cyanine dyes, merocyanine dyes, croconium dyes, squarylium dyes, azulenium dyes, polymethine dyes, naphthoquinone dyes, pyrylium dyes, phthalocyanine dyes, naphthalocyanine dyes, naphtholactam dyes, azo dyes, condensed azo dyes, indigoid dyes, perinone dyes, perylene dyes, dioxazine dyes, quinacridone dyes, isoindolinone dyes, quinophthalone dyes, pyrrole dyes, thioindigo dyes, metal complex dyes (metal complex salt dyes), dithiol metal complex dyes, indoxyl dyes, triarylmethane dyes, anthraquinone dyes, naphthol dyes, azomethine dyes, benzimidazolone dyes, pyranthrone dyes, and threne dyes, etc. can be exemplified.

[0318] As the inorganic pigments, for example, carbon black, cobalt dyes, iron dyes, chromium dyes, titanium dyes, vanadium dyes, zirconium dyes, molybdenum dyes, ruthenium dyes, platinum dyes, ITO (indium tin oxide) dyes, ATO (antimony tin oxide) dyes, etc. can be exemplified.

[0319] The colorant (I) contained in the composition (III-1) and the film for forming a thermosetting protective film can be only one, or two or more, and the combination and ratio thereof can be arbitrarily selected.

[0320] When the colorant (I) is used, the content of the colorant (I) in the film for forming a thermosetting protective film can be appropriately adjusted depending on the purpose. For example, by adjusting the content of the colorant (I) in the film for forming a thermosetting protective film, the light transmittance of the protective film is adjusted, and thus the visibility of the laser printing on the protective film can be adjusted. Further, by adjusting the content of the colorant (I) in the film for forming a thermosetting protective film, the design property of the protective film can be improved, or the grinding marks on the back surface of the semiconductor wafer can be made less visible. In view of these points, in the composition (III-1), the proportion of the content of the colorant (I) with respect to the total content of all components except the solvent (i.e., the proportion of the content of the colorant (I) in the film for forming a thermosetting protective film with respect to the total mass of the film for forming a thermosetting protective film) is preferably 0.1 to 10% by mass, more preferably 0.1 to 7.5% by mass, and particularly preferably 0.1 to 5% by mass. By making the proportion be the lower limit value or more, the effects brought by the use of the colorant (I) can be more significantly obtained. Further, by making the proportion be the upper limit value or less, excessive decrease in the light transmittance of the film for forming a thermosetting protective film can be suppressed.

[0321] [General additives (J)]

[0322] The composition (III-1) and the film for forming a thermosetting protective film can contain a general additive (J) within a range not impairing the effects of the present application.

[0323] The general additive (J) can be a publicly known additive, and can be arbitrarily selected depending on the purpose, and is not particularly limited, and as a preferred additive, for example, plasticizers, antistatic agents, antioxidants, gettering agents, ultraviolet absorbers, and the like can be exemplified.

[0324] The general additive (J) contained in the composition (III-1) and the film for forming a thermosetting protective film can be only one, or two or more, and when two or more, the combination and ratio thereof can be arbitrarily selected.

[0325] The content of the general additive (J) of the composition (III-1) and the film for forming a thermosetting protective film is not particularly limited, and can be appropriately selected depending on the purpose.

[0326] [Solvent]

[0327] The composition (III-1) preferably further contains a solvent. The operability of the composition (III-1) containing a solvent is good.

[0328] The solvent is not particularly limited, and as a preferred solvent, for example, hydrocarbons such as toluene, xylene, and the like; alcohols such as methanol, ethanol, 2-propanol, isobutyl alcohol (2-methylpropane-l-ol), 1-butanol, and the like; esters such as ethyl acetate, and the like; ketones such as acetone, methyl ethyl ketone, and the like; ethers such as tetrahydrofuran, and the like; amides (compounds having an amide bond) such as dimethylformamide, N-methylpyrrolidone, and the like, and the like can be exemplified.

[0329] The solvent contained in the composition (III-1) can be only one, or two or more, and when two or more, the combination and ratio thereof can be arbitrarily selected.

[0330] From the viewpoint that the components contained in the composition (III-1) can be more uniformly mixed, as a more preferred solvent contained in the composition (III-1), for example, methyl ethyl ketone, toluene, ethyl acetate, and the like can be exemplified.

[0331] The content of the solvent of the composition (III-1) is not particularly limited, and for example, can be appropriately selected depending on the kind of the components other than the solvent.

[0332] [Method for producing a composition for forming a thermosetting protective film]

[0333] The composition for forming a thermosetting protective film such as the composition (III-1) can be obtained by blending each component for constituting the composition.

[0334] The thermosetting protective film-forming composition can be prepared by the same method as the adhesive composition described above, except that the kind of the blended component is different.

[0335] ◎ Energy ray-curable protective film-forming film

[0336] The curing conditions when the energy ray-curable protective film-forming film is attached to the target position of the workpiece and is cured by energy rays to form a protective film are not particularly limited as long as the protective film is cured to a degree that is sufficient to exhibit its function, and are appropriately selected depending on the kind of the energy ray-curable protective film-forming film.

[0337] For example, when the energy ray-curable protective film-forming film is cured by energy rays, the irradiance of the energy rays is preferably 120 to 280 mW / cm 2 . Also, the light amount of the energy rays at the time of curing is preferably 100 to 1000 mJ / cm 2 .

[0338] As the energy ray-curable protective film-forming film, for example, a film containing the energy ray-curable component (a) can be cited, and a film containing the energy ray-curable component (a) and a filler material is preferable.

[0339] In the energy ray-curable protective film-forming film, the energy ray-curable component (a) is preferably uncured, preferably has adhesiveness, and more preferably is uncured and has adhesiveness.

[0340] <Energy ray-curable protective film-forming composition (IV-1)>

[0341] As the preferable energy ray-curable protective film-forming composition, for example, the energy ray-curable protective film-forming composition (IV-1) containing the energy ray-curable component (a) (in the present specification, sometimes abbreviated as "composition (IV-1)", and the like can be cited.

[0342] [Energy ray-curable component (a)]

[0343] The energy ray-curable component (a) is a component that is cured by irradiation of energy rays, and is a component that imparts film-forming properties and flexibility and the like to the energy ray-curable protective film-forming film, and is used to form a hard protective film after curing.

[0344] As the energy ray-curable component (a), for example, a polymer (al) having an energy ray-curable group and having a weight average molecular weight of 80,000 to 2,000,000 and a compound (a2) having an energy ray-curable group and having a molecular weight of 100 to 80,000 can be exemplified. At least a part of the polymer (al) can be crosslinked by a crosslinking agent or can not be crosslinked.

[0345] (al) having an energy ray-curable group and having a weight average molecular weight of 80,000 to 2,000,000

[0346] As the polymer (al) having an energy ray-curable group and having a weight average molecular weight of 80,000 to 2,000,000, for example, an acrylic resin (al-1) obtained by reacting an acrylic polymer (all) having a functional group capable of reacting with a group possessed by another compound and an energy ray-curable compound (a12) having a group capable of reacting with the functional group and an energy ray-curable group such as an energy ray-curable double bond can be exemplified.

[0347] As the functional group capable of reacting with a group possessed by another compound, for example, a hydroxyl group, a carboxyl group, an amino group, a substituted amino group (a group in which one or both of the hydrogen atoms of an amino group is substituted with a group other than a hydrogen atom), an epoxy group and the like can be exemplified. However, from the viewpoint of preventing corrosion of a circuit of a workpiece or a workpiece processed product or the like, the functional group is preferably a group other than a carboxyl group.

[0348] Among them, the functional group is preferably a hydroxyl group.

[0349] • Acrylic polymer (all) having a functional group

[0350] As the acrylic polymer (all) having a functional group, for example, a polymer obtained by copolymerizing an acrylic monomer having the functional group and an acrylic monomer not having the functional group, and a polymer obtained by further copolymerizing a monomer other than an acrylic monomer (a non-acrylic monomer) in addition to these monomers can be exemplified.

[0351] Further, the acrylic polymer (all) can be a random copolymer or a block copolymer, and a polymerization method can employ a publicly known method.

[0352] As the acrylic monomer having the functional group, for example, a hydroxyl group-containing monomer, a carboxyl group-containing monomer, an amino group-containing monomer, a substituted amino group-containing monomer, an epoxy group-containing monomer and the like can be exemplified.

[0353] As the hydroxyl group-containing monomer, for example, a hydroxy methyl (meth) acrylate, a 2-hydroxyethyl (meth) acrylate, a 2-hydroxypropyl (meth) acrylate, a 3-hydroxypropyl (meth) acrylate, a 2-hydroxybutyl (meth) acrylate, a 3-hydroxybutyl (meth) acrylate, a 4-hydroxybutyl (meth) acrylate, and the like (hydroxyalkyl (meth) acrylate); a vinyl alcohol, an allyl alcohol, and the like (non-(meth) acryl unsaturated alcohol (unsaturated alcohol not having a (meth) acryl skeleton)); and the like can be exemplified.

[0354] As the carboxyl group-containing monomer, for example, an (meth) acrylic acid, a crotonic acid, and the like (ethylenically unsaturated monocarboxylic acid (monocarboxylic acid having an ethylenically unsaturated bond)); a fumaric acid, an itaconic acid, a maleic acid, a citraconic acid, and the like (ethylenically unsaturated dicarboxylic acid (dicarboxylic acid having an ethylenically unsaturated bond)); an anhydride of the ethylenically unsaturated dicarboxylic acid; a 2-carboxyethyl (meth) acrylate, and the like (carboxyalkyl (meth) acrylate); and the like can be exemplified.

[0355] The acrylic monomer having the functional group is preferably a hydroxyl group-containing monomer.

[0356] The acrylic monomer having the functional group constituting the acrylic polymer (a11) can be only one, or two or more, and in the case of two or more, the combination and ratio thereof can be arbitrarily selected.

[0357] As the acrylic monomer not having the functional group, for example, a methyl (meth) acrylate, an ethyl (meth) acrylate, a n-propyl (meth) acrylate, an isopropyl (meth) acrylate, a n-butyl (meth) acrylate, an isobutyl (meth) acrylate, a sec-butyl (meth) acrylate, a t-butyl (meth) acrylate, a pentyl (meth) acrylate, a hexyl (meth) acrylate, a heptyl (meth) acrylate, a 2-ethylhexyl (meth) acrylate, an isooctyl (meth) acrylate, a n-octyl (meth) acrylate, a n-nonyl (meth) acrylate, an isononyl (meth) acrylate, a decyl (meth) acrylate, an undecyl (meth) acrylate, a dodecyl (meth) acrylate ((meth) acrylate lauryl ester), a tridecyl (meth) acrylate, a tetradecyl (meth) acrylate ((meth) acrylate myristyl ester), a pentadecyl (meth) acrylate, a hexadecyl (meth) acrylate ((meth) acrylate palmitoyl ester), a heptadecyl (meth) acrylate, a stearyl (meth) acrylate ((meth) acrylate stearyl ester), and the like (alkyl ester of (meth) acrylate) in which the alkyl group constituting the alkyl ester is a chain structure having 1 to 18 carbon atoms can be exemplified.

[0358] Further, as the acrylic monomer not having the functional group, for example, (meth) methoxy methyl acrylate, (meth) methoxy ethyl acrylate, (meth) ethoxy methyl acrylate, (meth) ethoxy ethyl acrylate, and the like containing an alkoxyalkyl group; (meth) acrylate having an aromatic group such as (meth) phenyl acrylate; non-crosslinking (meth) acrylamide and a derivative thereof; non-crosslinking (meth) acrylate having a tertiary amino group such as (meth) acrylate N,N-dimethylaminoethyl, (meth) acrylate N,N-dimethylaminopropyl, and the like can be exemplified.

[0359] The acrylic monomer not having the functional group constituting the acrylic polymer (a11) can be only one, or two or more, and in the case of two or more, the combination and the ratio thereof can be arbitrarily selected.

[0360] As the non-acrylic monomer, for example, an olefin such as ethylene, norbornene, and the like; vinyl acetate; styrene, and the like can be exemplified.

[0361] The non-acrylic monomer constituting the acrylic polymer (a11) can be only one, or two or more, and in the case of two or more, the combination and the ratio thereof can be arbitrarily selected.

[0362] In the acrylic polymer (a11), the proportion (content) of the structural unit derived from the acrylic monomer having the functional group with respect to the total amount of the structural units constituting the polymer is preferably 0.1 to 50% by mass, more preferably 1 to 40% by mass, and particularly preferably 3 to 30% by mass. By making the proportion within the above range, in the acrylic resin (a1-1) obtained by copolymerization of the acrylic polymer (a11) and the energy ray-curable compound (a12), the content of the energy ray-curable group can be easily adjusted to a preferable range to adjust the degree of curing of the protective film.

[0363] The acrylic polymer (a11) constituting the acrylic resin (a1-1) can be only one, or two or more, and in the case of two or more, the combination and the ratio thereof can be arbitrarily selected.

[0364] In the composition (IV-1), the proportion of the content of the acrylic resin (a1-1) with respect to the total content of the components other than the solvent (i.e., the proportion of the content of the acrylic resin (a1-1) in the energy ray-curable protective film-forming film with respect to the total mass of the film) is preferably 1 to 70% by mass, more preferably 5 to 60% by mass, and particularly preferably 10 to 50% by mass.

[0365] • Energy ray-curable compound (a12)

[0366] The energy-curable compound (a12) preferably has one or more groups selected from the group consisting of isocyanate groups, epoxy groups, and carboxyl groups as functional groups capable of reacting with the functional groups of the acrylic polymer (a11), and more preferably has an isocyanate group as the functional group. For example, when the energy-curable compound (a12) has an isocyanate group as the functional group, the isocyanate group readily reacts with the hydroxyl group of the acrylic polymer (a11) having a hydroxyl group as the functional group.

[0367] The number of energy-curing groups in one molecule of the energy-curing compound (a12) is not particularly limited; for example, appropriate selection can be made based on physical properties such as shrinkage required for the target protective film.

[0368] For example, the energy-curing compound (a12) preferably has 1 to 5 energy-curing groups in one molecule, more preferably 1 to 3 energy-curing groups.

[0369] Examples of energy-curable compounds (a12) include 2-methacryloyloxyethyl isocyanate, m-isopropenyl-α,α-dimethylbenzyl isocyanate, methacryloyl isocyanate, allyl isocyanate, and 1,1-(bisacryloyloxymethyl)ethyl isocyanate.

[0370] Acryloyl monoisocyanate compounds are obtained by reacting diisocyanate compounds or polyisocyanate compounds with hydroxyethyl (meth)acrylate.

[0371] Acryloyl monoisocyanate compounds, etc., are obtained by reacting diisocyanate compounds or polyisocyanate compounds with polyol compounds and hydroxyethyl (meth)acrylate.

[0372] The energy-curable compound (a12) is preferably 2-methacryloyloxyethyl isocyanate.

[0373] The energy-curable compound (a12) constituting the acrylic resin (a1-1) may be only one type or two or more types. When there are two or more types, their combination and ratio can be arbitrarily selected.

[0374] The ratio of the content of the energy ray-curable group from the energy ray-curable compound (a12) to the content of the functional group from the acrylic polymer (a11) in the acrylic resin (a1-1) is preferably 20 to 120 mol%, more preferably 35 to 100 mol%, and particularly preferably 50 to 100 mol%. By making the ratio of the contents within the above range, the adhesion of the cured product of the energy ray-curable protective film-forming film is further increased. In addition, when the energy ray-curable compound (a12) is a monofunctional (one molecule has one of the groups) compound, the upper limit of the ratio of the contents is 100 mol%, but when the energy ray-curable compound (a12) is a polyfunctional (one molecule has two or more of the groups) compound, the upper limit of the ratio of the contents sometimes exceeds 100 mol%.

[0375] The weight average molecular weight (Mw) of the polymer (a1) is preferably 100000 to 2000000, and more preferably 300000 to 1500000.

[0376] wherein the "weight average molecular weight" is the weight average molecular weight described above.

[0377] When at least a part of the polymer (a1) is crosslinked by a crosslinking agent, the polymer (a1) can be a polymer in which a monomer other than any of the above-described monomers described as a monomer constituting the acrylic polymer (a11) and having a group that reacts with a crosslinking agent is polymerized and is crosslinked at the group that reacts with the crosslinking agent, and can be a polymer in which a group that reacts with the functional group from the energy ray-curable compound (a12) is crosslinked.

[0378] The polymer (a1) contained in the composition (IV-1) and the energy ray-curable protective film-forming film can be only one kind, or two or more kinds, and when two or more kinds are used, the combination and the ratio thereof can be arbitrarily selected.

[0379] (Compound (a2) having an energy ray-curable group and having a molecular weight of 100 to 80000)

[0380] As the energy ray-curable group in the compound (a2) having an energy ray-curable group and having a molecular weight of 100 to 80000, a group containing an energy ray-curable double bond can be exemplified, and as a preferable group, a (meth)acryloyl group, a vinyl group, and the like can be exemplified.

[0381] The compound (a2) is not particularly limited as long as the above conditions are satisfied, and low-molecular-weight compounds having an energy ray-curable group, epoxy resins having an energy ray-curable group, phenol resins having an energy ray-curable group, and the like can be exemplified.

[0382] As the low-molecular-weight compound having an energy ray-curable group in the compound (a2), for example, multifunctional monomers or oligomers, and the like, preferably acrylate compounds having a (meth)acryloyl group can be exemplified.

[0383] As the acrylate compound, for example, 2-hydroxy-3-(meth)acryloyloxypropyl methacrylate, polyethylene glycol di(meth)acrylate, propoxylated ethoxylated bisphenol A di(meth)acrylate, 2,2-bis[4-((meth)acryloyloxypolyethoxy)phenyl]propane, ethoxylated bisphenol A di(meth)acrylate, 2,2-bis[4-((meth)acryloyloxydiethoxy)phenyl]propane, 9,9-bis[4-(2-(meth)acryloyloxyethoxy)phenyl]fluorene, 2,2-bis[4-((meth)acryloyloxypolypropoxy)phenyl]propane, tricyclodecane dimethanol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, polytetramethylene glycol di(meth)acrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, 2,2-bis[4-((meth)acryloyloxyethoxy)phenyl]propane, neopentyl glycol di(meth)acrylate, ethoxylated polypropylene glycol di(meth)acrylate, 2-hydroxy-1,3-bis(meth)acryloyloxypropane, and the like difunctional (meth)acrylates can be exemplified.

[0384] tris(2-(meth)acryloyloxyethyl) isocyanurate, ε-caprolactone-modified tris(2-(meth)acryloyloxyethyl) isocyanurate, ethoxylated glycerol tri(meth)acrylate, pentaerythritol tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, ethoxylated pentaerythritol tetra(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol poly(meth)acrylate, dipentaerythritol hexa(meth)acrylate, and the like multifunctional (meth)acrylates;

[0385] multifunctional (meth)acrylate oligomers such as urethane (meth)acrylate oligomers, and the like.

[0386] As the epoxy resin having an energy ray-curable group in the compound (a2), a phenol resin having an energy ray-curable group, for example, the resin described in paragraph 0043 and the like of "Japanese Patent Application Laid-Open No. 2013-194102" can be used. The above resin also belongs to the resin constituting the thermosetting component described later, but it is regarded as the compound (a2) in the present application.

[0387] The weight average molecular weight of the compound (a2) is preferably 100 to 30,000, more preferably 300 to 10,000.

[0388] The compound (a2) contained in the composition (IV-1) and the energy ray-curable protective film-forming film can be only one, or two or more, and in the case of two or more, the combination and the ratio thereof can be arbitrarily selected.

[0389] [Polymer (b) not having an energy ray-curable group]

[0390] When the composition (IV-1) and the energy ray-curable protective film-forming film contain the compound (a2) as the energy ray-curable component (a), it is preferable to further contain a polymer (b) not having an energy ray-curable group.

[0391] At least a part of the polymer (b) can be crosslinked by a crosslinking agent, or can not be crosslinked.

[0392] As the polymer (b) not having an energy ray-curable group, for example, an acrylic polymer, a phenoxy resin, a urethane resin, a polyester, a rubber-based resin, an acrylic urethane resin, and the like can be exemplified.

[0393] Among them, the polymer (b) is preferably an acrylic polymer (hereinafter, sometimes abbreviated as "acrylic polymer (b-1)").

[0394] The acrylic polymer (b-1) is a publicly known component, and for example, it can be a homopolymer of one kind of acrylic monomer, or a copolymer of two or more kinds of acrylic monomers, or a copolymer of one or two or more kinds of acrylic monomers and one or two or more kinds of monomers other than the acrylic monomer (monomers other than acrylic monomers).

[0395] As the acrylic monomer constituting the acrylic polymer (b-1), for example, an alkyl (meth)acrylate, a (meth)acrylate having a cyclic skeleton, a (meth)acrylate containing a glycidyl group, a (meth)acrylate containing a hydroxyl group, a (meth)acrylate containing a substituted amino group, and the like can be exemplified. Among them, the "substituted amino group" is the substituted amino group described earlier.

[0396] As the (meth)acrylic acid alkyl ester, for example, the same (meth)acrylic acid alkyl ester as the aforementioned acrylic acid monomer (alkyl group constituting the alkyl ester is a chain structure having 1 to 18 carbon atoms, such as (meth)acrylic acid alkyl ester) constituting the acrylic acid polymer (a11) not having the functional group can be exemplified.

[0397] As the (meth)acrylic acid ester having a cyclic skeleton, for example, (meth)acrylic acid isobornyl ester, (meth)acrylic acid dicyclopentyl ester, and the like (meth)acrylic acid cycloalkyl ester can be exemplified.

[0398] (meth)acrylic acid benzyl ester, and the like (meth)acrylic acid aralkyl ester;

[0399] (meth)acrylic acid dicyclopentenyl ester, and the like (meth)acrylic acid cycloalkenyl ester;

[0400] (meth)acrylic acid dicyclopentenyl oxyethyl ester, and the like (meth)acrylic acid cycloalkenyloxyalkyl ester, and the like.

[0401] As the (meth)acrylic acid ester having a glycidyl group, for example, (meth)acrylic acid glycidyl ester, and the like can be exemplified.

[0402] As the (meth)acrylic acid ester having a hydroxyl group, for example, (meth)acrylic acid hydroxymethyl ester, (meth)acrylic acid 2-hydroxyethyl ester, (meth)acrylic acid 2-hydroxypropyl ester, (meth)acrylic acid 3-hydroxypropyl ester, (meth)acrylic acid 2-hydroxybutyl ester, (meth)acrylic acid 3-hydroxybutyl ester, (meth)acrylic acid 4-hydroxybutyl ester, and the like can be exemplified.

[0403] As the (meth)acrylic acid ester having a substituted amino group, for example, (meth)acrylic acid N-methylaminoethyl ester, and the like can be exemplified.

[0404] As the non-acrylic acid monomer constituting the acrylic acid polymer (b-1), for example, an olefin such as ethylene, norbornene, vinyl acetate, and styrene can be exemplified.

[0405] As the polymer (b) not having an energy ray-curable group, at least a part of which is crosslinked by a crosslinking agent, for example, a polymer obtained by reacting a reactive functional group in the polymer (b) with a crosslinking agent can be exemplified.

[0406] The reactive functional group is not particularly limited as long as it is appropriately selected depending on the type of the crosslinking agent, etc. For example, when the crosslinking agent is a polyisocyanate compound, as the reactive functional group, a hydroxyl group, a carboxyl group, an amino group, etc. can be exemplified, of which a hydroxyl group having high reactivity with an isocyanate group is preferable. Further, when the crosslinking agent is an epoxy compound, as the reactive functional group, a carboxyl group, an amino group, an amide group, etc. can be exemplified. Of these, a carboxyl group having high reactivity with an epoxy group is preferable. However, from the viewpoint of preventing corrosion of a circuit of a workpiece or a workpiece processed product, the reactive functional group is preferably a group other than a carboxyl group.

[0407] As the polymer (b) having the reactive functional group and not having an energy ray-curable group, for example, a polymer obtained by polymerizing a monomer having at least the reactive functional group can be exemplified. When it is an acrylic polymer (b-1), as the monomer having the reactive functional group, any one or both of the acrylic monomer and the non-acrylic monomer exemplified as the monomer constituting the acrylic polymer (b-1) can be used. As the polymer (b) having a hydroxyl group as the reactive functional group, for example, a polymer obtained by polymerizing a (meth)acrylate having a hydroxyl group can be exemplified, and in addition thereto, a polymer obtained by polymerizing one or two or more of the monomers exemplified above in which a hydrogen atom of the acrylic monomer or the non-acrylic monomer is substituted with the reactive functional group can be exemplified.

[0408] In the polymer (b) having the reactive functional group, the proportion (content) of the structural unit derived from the monomer having the reactive functional group with respect to the total amount of the structural units constituting the polymer is preferably 1 to 20% by mass, and more preferably 2 to 10% by mass. By making the proportion within the above range, in the polymer (b), the degree of crosslinking becomes a more preferable range.

[0409] From the viewpoint of making the film-forming property of the composition (IV-1) better, the weight average molecular weight (Mw) of the polymer (b) not having an energy ray-curable group is preferably 10,000 to 2,000,000, and more preferably 100,000 to 1,500,000. Here, the "weight average molecular weight" is the weight average molecular weight described above.

[0410] The polymer (b) not having an energy ray-curable group contained in the composition (IV-1) and the energy ray-curable protective film-forming film can be only one kind, or two or more kinds, and when it is two or more kinds, the combination and the ratio thereof can be arbitrarily selected.

[0411] As the composition (IV-1), a composition containing either or both of the polymer (al) and the compound (a2) can be exemplified. Also, when the composition (IV-1) contains the compound (a2), it is preferable to further contain a polymer (b) having no energy ray-curable group, and in this case, it is further preferable to contain the (al) as well. Further, the composition (IV-1) can also contain the polymer (al) and the polymer (b) having no energy ray-curable group without containing the compound (a2).

[0412] When the composition (IV-1) contains the polymer (al), the compound (a2) and the polymer (b) having no energy ray-curable group, in the composition (IV-1), the content of the compound (a2) is preferably 10 to 400 parts by mass, more preferably 30 to 350 parts by mass, with respect to 100 parts by mass of the total content of the polymer (al) and the polymer (b) having no energy ray-curable group.

[0413] In the composition (IV-1), the ratio of the total content of the energy ray-curable component (a) and the polymer (b) having no energy ray-curable group with respect to the total content of the components other than the solvent (i.e., the ratio of the total content of the energy ray-curable component (a) and the polymer (b) having no energy ray-curable group in the film for forming an energy ray-curable protective film with respect to the total mass of the film) is preferably 5 to 90% by mass, more preferably 10 to 80% by mass, and particularly preferably 20 to 70% by mass. By making the ratio of the content of the energy ray-curable component to be within the above range, the energy ray curability of the film for forming an energy ray-curable protective film becomes better.

[0414] The composition (IV-1) can contain, in addition to the energy ray-curable component, one or two or more components selected from the group consisting of a thermosetting component, a filler material, a coupling agent, a crosslinking agent, a photopolymerization initiator, a colorant and a general-purpose additive, according to the purpose.

[0415] As the thermosetting component, the filler material, the coupling agent, the crosslinking agent, the photopolymerization initiator, the colorant and the general-purpose additive in the composition (IV-1), the same components as the thermosetting component (B), the filler material (D), the coupling agent (E), the crosslinking agent (F), the photopolymerization initiator (H), the colorant (I) and the general-purpose additive (J) in the composition (III-1) can be exemplified, respectively.

[0416] For example, by using the composition (IV-1) containing the energy ray-curable component and the thermosetting component, the adhesion of the energy ray-curable protective film forming film to the adherend is improved by heating, and the strength of the protective film formed from the energy ray-curable protective film forming film is also improved.

[0417] Further, by using the composition (IV-1) containing the energy ray-curable component and the colorant, the energy ray-curable protective film forming film formed exhibits the same effects as when the thermosetting protective film forming film contains the colorant (I) as described above.

[0418] In the composition (IV-1), the thermosetting component, the filler, the coupling agent, the crosslinking agent, the photopolymerization initiator, the colorant, and the general-purpose additive can each be used singly, or two or more kinds can be used at the same time, and the combination and the ratio thereof can be arbitrarily selected when two or more kinds are used at the same time.

[0419] The content of the thermosetting component, the coupling agent, the crosslinking agent, the photopolymerization initiator, the colorant, and the general-purpose additive in the composition (IV-1) is not particularly limited as long as it is appropriately adjusted according to the purpose.

[0420] The content of the filler in the composition (IV-1) is preferably 80% by mass or less, and is preferably 70% by mass or less, and for example, can be in any one of the ranges of 50% by mass or more and 80% by mass or less, and 55% by mass or more and 80% by mass or less, or can be in any one of the ranges of 50% by mass or more and 70% by mass or less, and 55% by mass or more and 70% by mass or less. By making the ratio be in the above ranges, the components are inhibited from moving between the energy ray-curable adhesive layer and the protective film forming film before the energy ray curing.

[0421] Since the handleability of the composition (IV-1) is improved by dilution, it is preferable to further contain a solvent.

[0422] As the solvent contained in the composition (IV-1), the same solvent as in the composition (III-1) can be cited, for example.

[0423] The solvent contained in the composition (IV-1) can be only one kind, or two or more kinds.

[0424] The content of the solvent in the composition (IV-1) is not particularly limited, and for example, is appropriately selected according to the kind of the component other than the solvent.

[0425] <Method for producing an energy ray-curable protective film forming composition>

[0426] The energy ray-curable protective film-forming composition (IV-1) or the like can be obtained by blending the respective components used to constitute the composition.

[0427] The energy ray-curable protective film-forming composition can be produced by the same method as the adhesive composition described above, except that the kind of the components to be blended is different.

[0428] Non-curable protective film-forming film

[0429] As the preferred non-curable protective film-forming film, for example, a film containing a thermoplastic resin and a filler material can be cited.

[0430] [Non-curable protective film-forming composition (V-1)]

[0431] As the preferred non-curable protective film-forming composition, for example, a non-curable protective film-forming composition (V-1) (in the present specification, sometimes abbreviated as "composition (V-1)") or the like containing the thermoplastic resin and the filler material can be cited.

[0432] [Thermoplastic resin]

[0433] The thermoplastic resin is not particularly limited.

[0434] As the thermoplastic resin, more specifically, for example, the same resins as the non-curable resins cited above as the contained components of the composition (III-1), such as an acrylic resin, a polyester, a polyurethane, a phenoxy resin, a polybutene, a polybutadiene, a polystyrene, or the like can be cited.

[0435] The thermoplastic resin contained in the composition (V-1) and the non-curable protective film-forming film can be only one kind, or two or more kinds, and in the case of two or more kinds, the combination and the ratio thereof can be arbitrarily selected.

[0436] In the composition (V-1), the proportion of the content of the thermoplastic resin with respect to the total content of the components other than the solvent (i.e., the proportion of the content of the thermoplastic resin in the non-curable protective film-forming film with respect to the total mass of the non-curable protective film-forming film) is preferably 25 to 75 mass%.

[0437] [Filler material]

[0438] The non-curable protective film-forming film containing the filler material exerts the same effect as the thermosetting protective film-forming film containing the filler material (D).

[0439] As the filler contained in the composition (V-1) and the non-cured protective film-forming film, the same filler as the filler (D) contained in the composition (III-1) and the thermosetting protective film-forming film can be exemplified.

[0440] The filler contained in the composition (V-1) and the non-cured protective film-forming film can be only one or two or more, and in the case of two or more, the combination and the ratio thereof can be arbitrarily selected.

[0441] In the composition (V-1), the proportion of the content of the filler with respect to the total content of all the components except the solvent (i.e., the proportion of the content of the filler in the non-cured protective film-forming film with respect to the total mass of the non-cured protective film-forming film) is preferably 50 to 75% by mass. By making the proportion within the above range, as in the case of using the composition (III-1), it becomes easier to adjust the coefficient of thermal expansion of the non-cured protective film-forming film (i.e., the protective film).

[0442] The composition (V-1) can contain other components in addition to the thermoplastic resin and the filler, as necessary.

[0443] The other components are not particularly limited and can be arbitrarily selected as necessary.

[0444] For example, by using the composition (V-1) containing the thermoplastic resin and the coloring agent, the non-cured protective film-forming film (in other words, the protective film) formed thereby exhibits the same effects as in the case where the thermosetting protective film-forming film contains the coloring agent (I) as described above.

[0445] In the composition (V-1), one kind of the other components can be used alone or two or more kinds thereof can be used at the same time, and in the case of two or more kinds, the combination and the ratio thereof can be arbitrarily selected.

[0446] The content of the other components of the composition (V-1) is not particularly limited and can be appropriately adjusted as necessary.

[0447] Since the handleability of the composition (V-1) is improved by dilution, it is preferred to further contain a solvent.

[0448] As the solvent contained in the composition (V-1), the same solvent as in the above-mentioned composition (III-1) can be exemplified.

[0449] The solvent contained in the composition (V-1) can be only one or two or more.

[0450] The content of the solvent of the composition (V-1) is not particularly limited and can be appropriately selected, for example, depending on the kind of the components other than the solvent.

[0451] <Method for producing non-curable protective film-forming composition>

[0452] The non-curable protective film-forming composition (V-1) or the like can be obtained by blending each component for constituting the composition.

[0453] The non-curable protective film-forming composition can be produced, for example, by the same method as the adhesive composition described above, except that the kind of the component to be blended is different.

[0454] As one embodiment of the protective film-forming composite sheet, for example, there can be cited a protective film-forming composite sheet provided with a substrate, and having an energy ray-curable adhesive layer and a protective film-forming film laminated in this order and in contact with each other on one face of the substrate, the adhesive layer having a gel fraction of 80% or more, the protective film-forming film having a glass transition temperature of 3°C or higher, the protective film-forming film having a loss modulus at 23°C of 3 MPa or less, and the protective film-forming film having a content of filler of 40% by mass or more with respect to the total mass of the protective film-forming film.

[0455] The content of the filler is 40% by mass or more with respect to the total mass of the protective film-forming film.

[0456] Further, as one embodiment of the protective film-forming composite sheet, for example, there can be cited a protective film-forming composite sheet provided with a substrate, and having an energy ray-curable adhesive layer and a protective film-forming film laminated in this order and in contact with each other on one face of the substrate, the adhesive layer having a gel fraction of 20% or more and less than 80%, the protective film-forming film having a glass transition temperature of 3°C or higher, the protective film-forming film having a loss modulus at 23°C of 3 MPa or more, and the protective film-forming film having a content of filler of 40% by mass or more with respect to the total mass of the protective film-forming film.

[0457] Method for producing protective film-forming composite sheet

[0458] The protective film-forming composite sheet can be produced by laminating the above-described layers in a positional relationship, and adjusting the shape of a part or all of the layers as needed. The method for forming each layer is the method for forming described above.

[0459] For example, in the production of a support sheet, when laminating the adhesive layer on the substrate, it is only necessary to apply the above-described adhesive composition on the substrate and dry it as needed.

[0460] Further, the adhesive layer can be laminated on the substrate by a method in which the adhesive composition is applied on the release film and dried as desired to form an adhesive layer on the release film, and the exposed surface of the adhesive layer is attached to one surface of the substrate. In this case, the adhesive composition is preferably applied on the release-treated surface of the release film.

[0461] Further, the adhesive layer can be laminated on the substrate by a method in which the adhesive composition is applied on the release film and dried as desired to form an adhesive layer on the release film, and the exposed surface of the adhesive layer is attached to one surface of the substrate. In this case, the adhesive composition is preferably applied on the release-treated surface of the release film.

[0462] Further, the adhesive layer can be laminated on the substrate by a method in which the adhesive composition is applied on the release film and dried as desired to form an adhesive layer on the release film, and the exposed surface of the adhesive layer is attached to one surface of the substrate. In this case, the adhesive composition is preferably applied on the release-treated surface of the release film.

[0463] Further, the adhesive layer can be laminated on the substrate by a method in which the adhesive composition is applied on the release film and dried as desired to form an adhesive layer on the release film, and the exposed surface of the adhesive layer is attached to one surface of the substrate. In this case, the adhesive composition is preferably applied on the release-treated surface of the release film.

[0464] Further, the adhesive layer can be laminated on the substrate by a method in which the adhesive composition is applied on the release film and dried as desired to form an adhesive layer on the release film, and the exposed surface of the adhesive layer is attached to one surface of the substrate. In this case, the adhesive composition is preferably applied on the release-treated surface of the release film.

[0465] Further, the adhesive layer can be laminated on the substrate by a method in which the adhesive composition is applied on the release film and dried as desired to form an adhesive layer on the release film, and the exposed surface of the adhesive layer is attached to one surface of the substrate. In this case, the adhesive composition is preferably applied on the release-treated surface of the release film.

[0466] Further, the adhesive layer can be laminated on the substrate by a method in which the adhesive composition is applied on the release film and dried as desired to form an adhesive layer on the release film, and the exposed surface of the adhesive layer is attached to one surface of the substrate. In this case, the adhesive composition is preferably applied on the release-treated surface of the release film.

[0467] In addition, the protective film forming composite sheet is generally stored with a release film attached to the surface of the outermost layer (e.g., the protective film forming film) of the composite sheet on the opposite side from the support sheet. Therefore, by applying a composition for forming a layer constituting the outermost layer, etc., to the release film (preferably to the release treatment surface thereof) and drying it as necessary, a layer constituting the outermost layer is formed on the release film, and the remaining layers are layered on the exposed surface of the layer on the opposite side from the side in contact with the release film by any of the above-described methods, and the state of attachment to the release film is maintained without removing the release film, whereby a protective film forming composite sheet with a release film can be obtained.

[0468] ■Method for manufacturing a workpiece processed product with a protective film (method for using a protective film forming composite sheet)

[0469] The protective film forming composite sheet can be used in the manufacture of the workpiece processed product with a protective film.

[0470] As one example of a method for manufacturing a workpiece processed product with a protective film provided at an arbitrary position of the workpiece processed product, a method can be cited in which: an attaching step of producing a laminate of the protective film forming composite sheet provided (layered) on a workpiece by attaching the protective film forming film in the protective film forming composite sheet to a target position of the workpiece; a curing step of curing the protective film forming film as necessary after the attaching step; a printing step of printing on the protective film forming film or the cured product thereof in the protective film forming composite sheet in the laminate by irradiating laser from the outside of the support sheet side of the protective film forming composite sheet through the support sheet after the attaching step; and a processing step of producing a workpiece processed product by processing the workpiece after the printing step, in which the protective film forming film is attached to the workpiece and is directly used as a protective film without curing, or a cured product obtained by curing the protective film forming film is used as a protective film.

[0471] As one example of a method for manufacturing a workpiece-processed product with a protective film, i.e., a method for manufacturing a semiconductor chip with a protective film, when the workpiece is a semiconductor wafer, a method for manufacturing a semiconductor chip with a protective film, which is provided with a protective film on the back surface of the semiconductor chip, can be exemplified. The method for manufacturing a semiconductor chip with a protective film has: an attaching step of attaching a protective film forming film in a protective film forming composite sheet to the back surface of a semiconductor wafer, thereby producing a laminate in which the protective film forming composite sheet is provided on the back surface of the semiconductor wafer; a curing step of curing the protective film forming film after the attaching step, as needed; a lettering step of irradiating the protective film forming film or a cured product thereof in the protective film forming composite sheet in the laminate with laser light from the outside of the support sheet on the support sheet side of the protective film forming composite sheet, thereby performing lettering on the protective film forming film or the cured product thereof; a dividing / cutting step of producing a semiconductor chip by dividing the semiconductor wafer after the lettering step, and further cutting the protective film forming film or the cured product thereof; and a picking-up step of separating and picking up the semiconductor chip provided with the cut protective film forming film or the cured product thereof from the support sheet. In the method for manufacturing a semiconductor chip with a protective film, the protective film forming film is attached to the semiconductor wafer, and then, either the protective film forming film is directly used as a protective film without being cured, or a cured product obtained by curing the protective film forming film is used as a protective film.

[0472] In the method for manufacturing, when the workpiece is a semiconductor wafer, the workpiece can be used as described above.

[0473] In the method for manufacturing, by using the protective film forming composite sheet of the present embodiment described above, even when the laser light of a short wavelength such as 266 nm is irradiated, lettering can be favorably performed on the protective film forming film or the cured product thereof in the protective film forming composite sheet. Further, the lettering can be favorably recognized from the outside of the support sheet on the support sheet side of the protective film forming composite sheet.

[0474] The method for manufacturing can be classified into a method for manufacturing with the curing step (in the present specification, sometimes referred to as "manufacturing method (1)") and a method for manufacturing without the curing step (in the present specification, sometimes referred to as "manufacturing method (2)").

[0475] Hereinafter, these methods for manufacturing will be described in order.

[0476] "Manufacturing method (1)"

[0477] The manufacturing method (1) is a manufacturing method of a workpiece processed product provided with a protective film at an arbitrary position of a workpiece, and includes: an attaching step of producing a laminate in which the protective film forming composite sheet is provided (stacked) on the workpiece by attaching the protective film forming film in the protective film forming composite sheet to a target position of the workpiece; a curing step of curing the protective film forming film after the attaching step; a printing step of performing printing on the protective film forming film or the cured product thereof in the protective film forming composite sheet in the laminate by irradiating laser from the outside of the support sheet side of the protective film forming composite sheet after the attaching step; and a processing step of producing a workpiece processed product by processing the workpiece after the printing step, and in the manufacturing method (1), the cured product obtained by curing the protective film forming film after being attached to the workpiece is used as the protective film.

[0478] Figures 3-7 A cross-sectional view for illustrating one example of the manufacturing method (1) when the workpiece is a semiconductor wafer is shown. Here, the manufacturing method using the protective film forming composite sheet 101 shown in FIG. 1 is described. Figure 1

[0479] <Attaching Step>

[0480] In the attaching step, as the protective film forming composite sheet 101, a composite sheet from which the release film 15 is removed is used, and as shown in FIG. 2, the protective film forming film 13 in the protective film forming composite sheet 101 is attached to the back surface 9b of the semiconductor wafer 9. Thus, a laminate 901 composed of the semiconductor wafer 9 and the protective film forming composite sheet 101 provided on the back surface 9b thereof is produced. Figure 3

[0481] In the attaching step, the protective film forming film 13 can be softened by heating and attached to the semiconductor wafer 9.

[0482] In addition, here, in the semiconductor wafer 9, the illustration of bumps and the like on the circuit formation surface 9a is omitted.

[0483] Further, the symbol 13b indicates a surface (in this specification, sometimes referred to as a "second surface") of the protective film forming film 13 on the side opposite to the first surface 13a (in other words, the adhesive layer 12 side).

[0484] In order to set the thickness of the semiconductor wafer 9 to a target value, the back surface thereof can be ground. That is, the back surface 9b of the semiconductor wafer 9 can be a ground surface.

[0485] ​​In the semiconductor wafer 9, it is preferable that there is no through groove between the circuit formation surface 9a and the back surface 9b thereof.

[0486] <solidification step>

[0487] In the solidification step after the attaching step, as shown in Figure 4 the protective film formation film 13 is solidified.

[0488] Here, a case where the solidification step is performed before the lettering step is shown.

[0489] In the present embodiment, whether or not the solidification of the protective film formation film 13 after being attached to the semiconductor wafer 9 is cut off, the solidification is used as the protective film.

[0490] By performing the solidification step, the protective film formation composite sheet 101 becomes the protective film formation composite sheet 1011 in which the protective film formation film 13 becomes the solidification 13' thereof, and a solidified laminate 9011 constituted of the semiconductor wafer 9 and the protective film formation composite sheet 1011 provided on the back surface 9b thereof is obtained.

[0491] The symbol 13a' indicates a first surface of the solidification 13' corresponding to the first surface 13a of the protective film formation film 13, and the symbol 13b' indicates a second surface of the solidification 13' corresponding to the second surface 13b of the protective film formation film 13.

[0492] In the solidification step, when the protective film formation film 13 is thermosetting, the protective film formation film 13 is heated, and thereby the solidification 13' is formed. When the protective film formation film 13 is energy ray-curable, the protective film formation film 13 is irradiated with energy rays through the support sheet 10, and thereby the solidification 13' is formed.

[0493] In the solidification step, the solidification conditions of the protective film formation film 13, that is, the heating temperature and the heating time in the case of thermal curing and the irradiation and the light amount of energy rays in the case of energy ray curing are as described above.

[0494] <lettering step>

[0495] In the lettering step after the attaching step, as shown in Figure 5 the solidification 13' in the protective film formation composite sheet 1011 in the solidified laminate 9011 is irradiated with laser light L from the outside of the support sheet 10 side of the protective film formation composite sheet 1011, and thereby lettering is performed on the solidification 13'. The lettering is performed on the second surface 13b' of the solidification 13' (omitted from the drawing).

[0496] By performing the printing process, the composite sheet for protective film formation 1011 becomes a composite sheet for protective film formation 1012 provided with the printed cured product 13', and a printed and cured layered body 9012 provided with the semiconductor wafer 9 and the composite sheet for protective film formation 1012 provided on the back surface 9b thereof is obtained.

[0497] The wavelength of the laser L is preferably shorter than that of the prior art, and more preferably 266 nm.

[0498] <Segmentation / cutting process>

[0499] In the segmentation / cutting process after the printing process, as shown in Figure 6 the semiconductor wafer 9 is segmented, and further, the cured product 13' is cut.

[0500] By performing the segmentation / cutting process, a plurality of semiconductor chips 91 provided with a semiconductor chip 9' and the cut cured product 130' provided on the back surface 9b' of the semiconductor chip 9' are obtained. The plurality of semiconductor chips 91 with protective films are in a state where they are all arranged on one support sheet 10, and these semiconductor chips 91 with protective films and the support sheet 10 constitute a semiconductor chip group 910 with protective films.

[0501] The symbol 130a' indicates a first surface of the cut cured product 130' corresponding to the first surface 13a' of the cured product 13', and the symbol 130b' indicates a second surface of the cut cured product 130' corresponding to the second surface 13b' of the cured product 13'.

[0502] The symbol 9a' indicates a circuit formation surface of the semiconductor chip 9' corresponding to the circuit formation surface 9a of the semiconductor wafer 9.

[0503] The production of the semiconductor chip 9' based on the segmentation (in other words, singulation) of the semiconductor wafer 9 can be performed using a known method.

[0504] As the segmentation method of the semiconductor wafer 9, for example, blade dicing in which the semiconductor wafer 9 is cut using a blade, laser dicing in which the semiconductor wafer 9 is cut by laser irradiation, water dicing in which the semiconductor wafer 9 is cut by spraying water containing an abrasive, and the like, a method of cutting into the semiconductor wafer. It can be cut into the adhesive layer 12, and it can be cut into the base material 11. When cut into the adhesive layer 12, cutting chips are less likely to be generated. When cut into the base material 11, the expansibility at the time of expansion is improved.

[0505] When these methods are applied, for example, the division of the semiconductor wafer 9 and the cutting of the cured product 13' can be performed simultaneously by cutting the cured product 13' while the semiconductor wafer 9 is being divided.

[0506] As the method of dividing the semiconductor wafer 9, a method other than the above-described method of cutting into the semiconductor wafer can also be cited.

[0507] That is, in this method, first, a position of intended division is set inside the semiconductor wafer 9, and laser light is irradiated in a manner focused on the position as a focal point, thereby forming a modified layer inside the semiconductor wafer 9. Unlike other positions of the semiconductor wafer, the modified layer of the semiconductor wafer is modified by irradiation of laser light, and its strength is weakened. Therefore, by applying a force to the semiconductor wafer 9, a crack extending in both surface directions of the semiconductor wafer 9 is generated at the modified layer inside the semiconductor wafer 9, and becomes a starting point of division (cutting) of the semiconductor wafer 9. Then, a force is applied to the semiconductor wafer 9, and the semiconductor wafer 9 is divided at the position of the modified layer, and a semiconductor chip is produced. The method of dividing the semiconductor wafer 9 along with the formation of the above-described modified layer is called Stealth Dicing (registered trademark).

[0508] For example, the semiconductor wafer in which the modified layer is formed can be expanded in a direction parallel to its surface, and divided by applying a force. Thus, when the method of expanding the semiconductor wafer is applied, the division of the semiconductor wafer 9 and the cutting of the cured product 13' can be performed simultaneously by expanding the semiconductor wafer 9 together with the cured product 13' of the film for protecting film formation, and thereby cutting the cured product 13'. The cutting by expanding the cured product 13' is preferably performed at a low temperature of -20 to 5°C or the like.

[0509] When the division of the semiconductor wafer 9 and the cutting of the cured product 13' are not performed simultaneously, the cutting of the cured product 13' can be performed by a publicly known method separately from the division of the semiconductor wafer 9.

[0510] <Picking-up process>

[0511] In the picking-up process after the division / cutting process, as shown in Figure 7 the semiconductor chip 9' (semiconductor chip 91 with a protective film) provided with the cut cured product 130' is separated from the support sheet 10 and picked up. Here, the direction of picking-up is indicated by an arrow I.

[0512] The picking up of the semiconductor chip 91 with the protective film can be performed by a known method. For example, as the separation means 8 for separating the semiconductor chip 91 with the protective film from the support sheet 10, a vacuum collet or the like can be cited. Note that, among them, only the separation means 8 is not shown in cross section, and the same applies to the same figures hereafter.

[0513] Thus, the semiconductor chip 91 with the protective film as the target is obtained.

[0514] The picked-up semiconductor chip with the protective film is first of all, in the semiconductor chip 91 with the protective film that was once the object of the printing process, the clear printing is maintained on the second face 130b' of the cured product 130' after the cutting.

[0515] <Timing of performing the curing process>

[0516] Hitherto, although the case where the curing process is performed between the attaching process and the printing process has been described, in the manufacturing method (1), the timing of performing the curing process is not limited to this. For example, in the manufacturing method (1), the curing process can be performed at any timing after the printing process and the separation / cutting process, the separation / cutting process and the picking up process, or the picking up process.

[0517] When the curing process is performed after the attaching process and the printing process, in the printing process, from the outside of the support sheet 10 side of the support sheet 10 from the protective film forming composite sheet 101, the Figure 3 The protective film forming film 13 in the protective film forming composite sheet 101 in the laminate 901 shown in FIG. 13 is irradiated with the laser light L, whereby printing is performed on the protective film forming film 13. The printing is performed on the second face 13b of the protective film forming film 13 (omitted from the drawing).

[0518] The printing process at this time can be performed by the same method as the printing process described earlier, except that the irradiation object of the laser light L is the protective film forming film 13 instead of the cured product 13' of the protective film forming film 13.

[0519] <Other processes>

[0520] In addition to each of the processes of the attaching process, the curing process, the printing process, the separation / cutting process, and the picking up process, the manufacturing method (1) can have other processes that do not belong to any of these processes.

[0521] The kind of the other processes and the timing of performing the other processes can be arbitrarily selected according to the purpose, and are not particularly limited.

[0522] <Manufacturing method (2)>

[0523] As an example of the manufacturing method (2), one can be described as follows: a manufacturing method for a workpiece having a protective film at any position on the workpiece, comprising: an attachment step of attaching a protective film forming film in a protective film forming composite sheet to a target position on the workpiece, thereby creating a laminate on the workpiece having (layered) the protective film forming composite sheet; after the attachment step, irradiating the protective film forming film in the protective film forming composite sheet in the laminate with a laser from the outside of the support sheet side of the protective film forming composite sheet, thereby printing characters on the protective film forming film; and after the printing step, a processing step of manufacturing the workpiece by processing the workpiece, wherein the protective film forming film attached to the workpiece is not cured and is directly used as a protective film.

[0524] Regardless of the type of workpiece, manufacturing method (2) is the same as manufacturing method (1) except that it does not have the curing process and directly uses the protective film formed after being attached to the workpiece as the protective film. It also has the same effect as manufacturing method (1).

[0525] Thus far, although mainly for use Figure 1 The manufacturing method of the workpiece with protective film when the protective film forming composite sheet 101 is shown has been described, but the manufacturing method of the workpiece with protective film in this embodiment is not limited thereto.

[0526] For example, even when using Figure 2 The protective film forming composite sheet, etc. shown, except Figure 1 Composite sheets other than the protective film forming composite sheet 101 shown can also be used to manufacture workpieces with protective films using the same manufacturing method described above.

[0527] When using a protective film forming composite sheet of other embodiments, based on the difference in structure between the sheet and the protective film forming composite sheet 101, the above manufacturing method can be appropriately modified, altered, or deleted in terms of process addition, modification, or deletion, thereby manufacturing a workpiece with a protective film.

[0528] ◇Semiconductor device manufacturing method

[0529] After obtaining the workpiece with a protective film through the above manufacturing method, the workpiece with the protective film can be used to manufacture a semiconductor device using a known appropriate method, depending on its type. For example, when the workpiece with the protective film is a semiconductor chip with a protective film, a semiconductor package can be formed by flip-chip bonding the semiconductor chip with the protective film on the circuit surface of a substrate, and the target semiconductor device can be manufactured using the semiconductor package (illustration omitted).

[0530] Embodiments

[0531] Hereinafter, the present application will be described in more detail by specific embodiments. However, the present application is not limited by the embodiments shown below.

[0532] <Manufacturing raw materials of resin>

[0533] The formal names of the manufacturing raw materials of the resins abbreviated in the present embodiments and comparative examples are shown below.

[0534] MA: methyl acrylate

[0535] HEA: 2-hydroxyethyl acrylate

[0536] 2EHA: 2-ethylhexyl acrylate

[0537] MOI: 2-methacryloyloxyethyl isocyanate

[0538] BA: n-butyl acrylate

[0539] GMA: glycidyl methacrylate

[0540] VAc: vinyl acetate

[0541] AA: acrylic acid

[0542] HEMA: 2-hydroxyethyl methacrylate

[0543] <Manufacturing raw materials of protective film forming composition>

[0544] The raw materials for preparing the protective film forming composition are shown below.

[0545] [Polymer component (A)]

[0546] (A)-1: Acrylic polymer (weight average molecular weight 300000, glass transition temperature 6°C) obtained by copolymerizing MA (85 parts by mass) and HEA (15 parts by mass)

[0547] (A)-2: Acrylic polymer (weight average molecular weight 800000, glass transition temperature -28°C) obtained by copolymerizing BA (55 parts by mass), MA (10 parts by mass), GMA (20 parts by mass), and HEA (15 parts by mass)

[0548] [Thermosetting component (B1)]

[0549] (B1)-1: Bisphenol A type epoxy resin ("jER828" manufactured by Mitsubishi Chemical Corporation, epoxy equivalent 184-194 g / eq)

[0550] (B1)-2: Bisphenol A type epoxy resin ("jER 1055" manufactured by Mitsubishi Chemical Corporation, epoxy equivalent 800 to 900 g / eq)

[0551] (B1)-3: Dicyclopentadiene type epoxy resin ("EPICLON HP-7200HH" manufactured by DIC CORPORATION, epoxy equivalent 255 to 260 g / eq)

[0552] [Thermal curing agent (B2)]

[0553] (B2)-1: Thermally active latent epoxy resin curing agent dicyandiamide (manufactured by Mitsubishi Chemical Corporation, DICY7, active hydrogen equivalent 21 g / eq)

[0554] [Curing accelerator (C)]

[0555] (C)-1: 2-phenyl-4,5-dihydroxymethylimidazole ("CUREZOL 2PHZ-PW" manufactured by SHIKOKU CHEMICALS CORPORATION)

[0556] [Filler (D)]

[0557] (D)-1: Silica filler (fused quartz filler, average particle diameter 8 μm)

[0558] [Coupling agent (E)]

[0559] (E)-1: Silane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd., KBM503)

[0560] [Crosslinking agent (F)]

[0561] (F)-1: Isocyanate-based crosslinking agent ("CORONATE L" manufactured by TOSOH CORPORATION, trimethylolpropane toluene diisocyanate trimer adduct)

[0562] [Colorant (I)]

[0563] (I)-1: Pigment obtained by pigmentizing phthalocyanine-based blue pigment (Pigment Blue 15:3) 32 parts by mass, isoindolinone-based yellow pigment (Pigment Yellow 139) 18 parts by mass, and anthraquinone-based red pigment (Pigment Red 177) 50 parts by mass in such a manner that the total amount of the three pigments / styrene acrylic resin = 1 / 3 (mass ratio).

[0564] [Energy ray-curable resin (G)]

[0565] (G)-1: ε-caprolactone-modified tris-(2-acryloyloxyethyl) isocyanurate (A-9300-1CL manufactured by SHIN-NAKAMURA CHEMICAL CO., LTD., trifunctional ultraviolet-curable compound)

[0566] [Example 1]

[0567] Manufacture of support sheet

[0568] Manufacture of adhesive resin (I-2a)

[0569] To an acrylic polymer having a weight average molecular weight of 600000 which is a copolymer of 2EHA (42 parts by mass), VAc (40 parts by mass), and HEA (18 parts by mass), MOI was added (an amount such that the total moles of isocyanate groups in the MOI is 0.8 times the total moles of hydroxyl groups from the HEA in the acrylic polymer), and an addition reaction was performed at 50°C for 48 hours in an air stream to obtain the target adhesive resin (I-2a)-1.

[0570] Hereinafter, the acrylic polymer is sometimes referred to as “adhesive resin (I-1a)-1”.

[0571] Preparation of adhesive composition (I-2)

[0572] An energy ray-curable adhesive composition (I-2)-1 was prepared which contains the adhesive resin (I-2a)-1 (100 parts by mass), hexamethylene diisocyanate-based crosslinking agent (“CORONATE L” manufactured by TOSOH CORPORATION) (0.21 parts by mass), and photopolymerization initiator (“Irgacure 127” manufactured by BASF, 2-hydroxy-1-{4-[4-(2-hydroxy-2-methyl-propionyl)-benzyl]-phenyl}-2-methyl-propane-1-one) (3 parts by mass), further contains ethyl acetate as a solvent, and the total concentration of all components except the solvent is 30% by mass. In addition, the content of each of the components shown here other than ethyl acetate is the content of the target without the solvent.

[0573] Manufacture of support sheet

[0574] A release film (Lintec Corporation, "SP-PET381031", thickness 38 μm) in which one side of a polyethylene terephthalate film was subjected to a release treatment by silicone treatment was prepared. On the release-treated side of the release film, the above-obtained adhesive composition (I-2)-1 was applied, and heated and dried at 100°C for 2 minutes, thereby forming an energy ray-curable adhesive layer having a thickness of 5 μm. The gel fraction of the adhesive layer was 90%. In addition, the gel fraction of the adhesive layer was a measured value obtained using the method described above. The same was true in the examples and comparative examples that follow.

[0575] Then, a polypropylene film (1) (thickness 80 μm, colorless) was attached to the exposed side of the adhesive layer as a substrate, thereby producing a laminated sheet in which the substrate, the adhesive layer, and the release film were sequentially stacked in the thickness direction, i.e., a support sheet with a release film.

[0576] Production of a protective film-forming film

[0577] Preparation of a protective film-forming composition (III-1)

[0578] Polymer component (A)-1 (25.5 parts by mass), thermosetting components (B1)-1 (10.2 parts by mass), (B1)-2 (1.7 parts by mass), (B1)-3 (5.4 parts by mass), thermosetting agent (B2)-1 (0.4 parts by mass), curing accelerator (C)-1 (0.4 parts by mass), filler (D)-1 (54.1 parts by mass), coupling agent (E)-1 (0.3 parts by mass), and colorant (I)-1 (2.0 parts by mass) were dissolved or dispersed in a mixed solvent of methyl ethyl ketone, toluene, and ethyl acetate, and stirred at 23°C, thereby obtaining a thermosetting protective film-forming composition (III-1)-1 in which the total concentration of all components except for the solvent was 50% by mass. In addition, the amounts of the components shown here, except for the mixed solvent, are amounts of the target objects without the solvent.

[0579] The content of the filler in the thermosetting protective film-forming composition from which the solvent was removed was 54.1% by mass. In addition, the Tg of the protective film-forming composition was 23.5°C.

[0580] Production of a protective film-forming film

[0581] A release film (second release film, "SP-PET381031" manufactured by Lintec Corporation, thickness 38 μm) in which one side of a polyethylene terephthalate film was subjected to a release treatment by silicone treatment was prepared. On the release-treated side of the second release film, the above-obtained protective film-forming composition (III-1)-1 was applied and dried at 100°C for 2 minutes, thereby producing a heat- resistant protective film-forming film having a thickness of 25 μm.

[0582] The loss modulus E" of the above-obtained protective film-forming film was 51.6 MPa.

[0583] Further, a release film (first release film, "SP-PET381031" manufactured by Lintec Corporation, thickness 38 μm) was attached to the release-treated side of the above-obtained protective film-forming film, thereby obtaining a laminated film composed of the protective film-forming film, the first release film attached to one side of the protective film-forming film, and the second release film attached to the other side of the protective film-forming film.

[0584] "Manufacture of Protective Film-Forming Composite Sheet"

[0585] The release film was removed from the above-obtained support sheet. Further, the first release film was removed from the above-obtained laminated film. Further, the protective film-forming composite sheet composed of the substrate, the adhesive layer, the protective film-forming film, and the second release film laminated in this order in the thickness direction was manufactured by attaching the exposed side of the adhesive layer resulting from the removal of the release film to the exposed side of the protective film-forming film resulting from the removal of the first release film.

[0586] "Evaluation of Protective Film-Forming Composite Sheet"

[0587] Using the above protective film-forming composite sheet, an 8-inch mirror wafer was attached to the protective film-forming film. After the wafer and the protective film-forming composite sheet were heated at 130°C for 2 hours to cure the protective film-forming film to form a protective film, the wafer was left to stand to room temperature.

[0588] Then, the wafer surface was adsorbed and fixed to an adsorption stage, and the end portion of the support sheet was held by a manipulator. The release test was performed at a release angle of 180° and a release speed of 300 mm / min at the interface between the protective film and the support sheet. The release properties at the interface between the protective film and the support sheet were evaluated based on the following criteria.

[0589] A: The release was performed without any problem at the interface between the protective film and the support sheet.

[0590] B: Peeling at the interface between the protective film and the support sheet was possible, but zipping occurred at the time of peeling.

[0591] C: Peeling at the interface between the protective film and the support sheet was not possible, and peeling at the interface between the wafer and the protective film occurred.

[0592] Manufacture and Evaluation of Protective Film Forming Film and Protective Film Forming Composite Sheet

[0593] [Example 2]

[0594] In the preparation of the protective film forming composition, 29.6 parts by mass of the polymer component (A)-1 was used, and 50 parts by mass of the filler material (D)-1 was used, and otherwise, in the same manner as in Example 1, a protective film forming film and a protective film forming composite sheet were manufactured, and evaluation was performed.

[0595] The loss modulus E" of the above protective film forming film was 11.0 MPa.

[0596] The content of the filler material in the thermosetting protective film forming composition from which the solvent was removed was 50.0 mass%. Further, the Tg of the protective film forming composition was 13.0°C.

[0597] The results are shown in Table 1.

[0598] [Example 3]

[0599] In the preparation of the protective film forming composition, the polymer component (A)-2 (19.0 parts by mass) was used instead of the polymer component (A)-1 (25.5 parts by mass), and 60.6 parts by mass of the filler material (D)-1 was used, and otherwise, in the same manner as in Example 1, a support sheet, a protective film forming film, and a protective film forming composite sheet were manufactured, and evaluation was performed.

[0600] The loss modulus E" of the above protective film forming film was 2.2 MPa.

[0601] The content of the filler material in the thermosetting protective film forming composition from which the solvent was removed was 60.6 mass%. Further, the Tg of the protective film forming composition was 2.2°C.

[0602] [Example 4]

[0603] In the preparation of the protective film forming composition, the polymer component (A)-2 (25.5 parts by mass) was used instead of the polymer component (A)-1 (25.5 parts by mass), and 54.1 parts by mass of the filler material (D)-1 was used, and otherwise, in the same manner as in Example 1, a protective film forming film and a protective film forming composite sheet were manufactured, and evaluation was performed.

[0604] The loss modulus E" of the above-mentioned protective film forming film was 1.3 MPa.

[0605] The content of the filler in the solvent-removed thermosetting protective film forming composition was 54.1 mass%. Further, the Tg of the protective film forming composition was 1.7°C.

[0606] [Example 5]

[0607] The polymer component (A)-1 (35.98 parts by mass), the thermosetting component (Bl)-1 (11.24 parts by mass), (Bl)-2 (2.04 parts by mass), (Bl)-3 (7.48 parts by mass), the thermosetting agent (B2)-1 (0.48 parts by mass), the curing accelerator (C)-1 (0.48 parts by mass), the filler (D)-1 (40.0 parts by mass), the coupling agent (E)-1 (0.3 parts by mass), and the colorant (I)-1 (2.0 parts by mass) were dissolved or dispersed in a mixed solvent of methyl ethyl ketone, toluene, and ethyl acetate, and stirred at 23°C, whereby a thermosetting protective film forming composition (III-1)-1 in which the total concentration of all components except the solvent was 50 mass% was obtained. In addition, the blending amounts of the components shown here, except for the mixed solvent, are the amounts of the target without the solvent.

[0608] The content of the filler in the solvent-removed thermosetting protective film forming composition was 40.0 mass%. Further, the Tg of the protective film forming composition was 16.5°C.

[0609] Then, using the above-mentioned protective film forming composition, a protective film forming film and a protective film forming composite sheet were manufactured in the same manner as in Example 1, and evaluated.

[0610] The loss modulus E" of the above-mentioned protective film forming film was 18.4 MPa.

[0611] The results are shown in Table 1.

[0612] [Example 6]

[0613] A support sheet, a protective film forming film, and a protective film forming composite sheet were manufactured in the same manner as in Example 1, except that the energy ray-curable adhesive composition (I-2)-2 prepared by the method shown below was used instead of the energy ray-curable adhesive composition (I-2)-1 when manufacturing the support sheet, and the thickness of the adhesive layer was set to 10 μm instead of 5 μm, and evaluated. The gel fraction of the adhesive layer was 50%. Further, the loss modulus E" of the above-mentioned protective film forming film was 51.6 MPa.

[0614] The results are shown in Table 1.

[0615] Preparation of the adhesive resin (I-2a)

[0616] An acrylic polymer (100 parts by mass) having a weight average molecular weight of 300,000 as a copolymer of 2EHA (21 parts by mass), VAc (76 parts by mass), AA (1 part by mass), and HEMA (2 parts by mass) was mixed with a mixture of 2- and 6-functional urethane acrylates (72 parts by mass), a hexamethylene diisocyanate-based crosslinking agent ("CORONATE L" manufactured by TOSOH CORPORATION) (3 parts by mass), and a photopolymerization initiator ("Irgacure 127" manufactured by BASF, 2-hydroxy-l-{4-[4-(2-hydroxy-2-methyl-propionyl)-benzyl]-phenyl}-2-methyl-propane-l-one) (3 parts by mass), and the concentration was adjusted to 30% using ethyl acetate, thereby obtaining the target adhesive resin (I-2a)-2.

[0617] Preparation of the adhesive composition (I-2)-2

[0618] An energy ray-curable adhesive composition (I-2)-2 was prepared, which contained the adhesive resin (I-2a)-2 (100 parts by mass), a hexamethylene diisocyanate-based crosslinking agent ("CORONATE L" manufactured by TOSOH CORPORATION) (3 parts by mass), and a photopolymerization initiator ("Irgacure 127" manufactured by BASF, 2-hydroxy-l-{4-[4-(2-hydroxy-2-methyl-propionyl)-benzyl]-phenyl}-2-methyl-propane-l-one), and further contained ethyl acetate as a solvent, and the total concentration of all components except the solvent was 30% by mass. In addition, the blending amounts of the components shown here, except ethyl acetate, are the amounts of the target without the solvent.

[0619] The content of the filler in the solvent-removed thermosetting protective film-forming composition was 54.1% by mass. In addition, the Tg of the protective film-forming composition was 23.5°C.

[0620] The results are shown in Table 1.

[0621] [Example 7]

[0622] In the preparation of the protective film-forming composition, 29.6 parts by mass of the polymer component (A)-1 and 50 parts by mass of the filler (D)-1 were used, and otherwise, in the same manner as in Example 6, a protective film-forming film and a protective film-forming composite sheet were manufactured, and evaluated.

[0623] The loss modulus E" of the above-mentioned protective film forming film was 18.4 MPa.

[0624] The content of the filler in the thermosetting protective film forming composition from which the solvent was removed was 50.0 mass%. Further, the Tg of the protective film forming composition was 13.0°C.

[0625] The results are shown in Table 1.

[0626] [Example 8]

[0627] In the production of the support sheet, the adhesive composition (I-2)-2 was used in place of the energy ray-curable adhesive composition (I-2)-1, and otherwise, in the same manner as in Example 5, a protective film forming film and a protective film forming composite sheet were produced, and evaluated.

[0628] The loss modulus E" of the above-mentioned protective film forming film was 18.4 MPa.

[0629] The content of the filler in the thermosetting protective film forming composition from which the solvent was removed was 40.0 mass%. Further, the Tg of the protective film forming composition was 16.5°C.

[0630] The results are shown in Table 1.

[0631] [Example 9]

[0632] [Preparation of protective film forming composition (IV-1)]

[0633] The polymer component (A)-1 (27.07 parts by mass), the energy ray-curable resin (G)-1 (10.0 parts by mass), the crosslinking agent (F)-1 (0.77 parts by mass), the photopolymerization initiator ("Irgacure 369" manufactured by BASF, 2-benzyl-2-(dimethylamino)-1-(4-morpholinophenyl)-1-butanone) (0.6 parts by mass), the filler (D)-1 (56.65 parts by mass), the coupling agent (E)-1 (0.4 parts by mass), and the colorant (I)-1 (4.5 parts by mass) were dissolved or dispersed in a mixed solvent of methyl ethyl ketone, toluene, and ethyl acetate, and stirred at 23°C, whereby an energy ray-curable protective film forming composition (III-1)-1 was obtained, in which the total concentration of all the components except the solvent was 50 mass%. Note that the blending amounts of the components shown here, except the mixed solvent, are the amounts of the target objects without the solvent.

[0634] The content of the filler in the energy ray-curable protective film forming composition from which the solvent was removed was 56.7 mass%. Further, the Tg of the protective film forming composition was 6.2°C.

[0635] <Manufacture of the protective film forming film>

[0636] A release film (second release film, "SP-PET381031" manufactured by Lintec Corporation, thickness 38 μm) in which one side of a polyethylene terephthalate film was subjected to a release treatment by silicone treatment was used, and the protective film forming composition (III-1)-1 obtained above was applied on the release treated side of the second release film, and dried at 100°C for 2 minutes, thereby manufacturing a protective film forming film having a thickness of 25 μm.

[0637] The loss modulus E" of the protective film forming film obtained above was 5.8 MPa.

[0638] Further, the release treated side of a release film (first release film, "SP-PET381031" manufactured by Lintec Corporation, thickness 38 μm) was attached to the exposed side of the protective film forming film obtained above which did not have the second release film, thereby obtaining a laminated film composed of the protective film forming film, the first release film provided on one side of the protective film forming film, and the second release film provided on the other side of the protective film forming film.

[0639] <Manufacture of the protective film forming composite sheet>

[0640] The release film was removed from the support sheet obtained by the same method as in Example 1. Further, the first release film was removed from the laminated film obtained above. Then, the exposed side of the adhesive layer generated by removing the release film above was attached to the exposed side of the protective film forming film generated by removing the first release film above, thereby manufacturing a protective film forming composite sheet composed of a substrate, an adhesive layer, a protective film forming film, and a second release film, which were laminated in this order in the thickness direction thereof.

[0641] Then, the protective film forming composite sheet was cured by irradiating light having a wavelength of 365 nm three times under conditions in which the illuminance was 215 mW / cm 2 , and the light amount was 187 mJ / cm 2 , instead of curing it by heating at 30°C for 2 hours, and was evaluated by the same method as in Example 1.

[0642] The results are shown in Table 1

[0643] [Comparative Example 1]

[0644] In the preparation of the protective film forming composition, polymer component (A)-2 (19.0 parts by mass) was used instead of polymer component (A)-l (25.5 parts by mass), and 60.6 parts by mass of filler material (D)-l was used, and otherwise, in the same manner as in Example 6, a protective film forming film and a protective film forming composite sheet were produced, and evaluation was performed.

[0645] The loss modulus E" of the above protective film forming film was 2.2 MPa.

[0646] The content of the filler material in the solvent-removed thermosetting protective film forming composition was 60.6 mass%. Further, the Tg of the protective film forming composition was 2.2°C.

[0647] The results are shown in Table 1.

[0648] [Comparative Example 2]

[0649] In the preparation of the protective film forming composition, polymer component (A)-2 (25.5 parts by mass) was used instead of polymer component (A)-l (25.5 parts by mass), and 54.1 parts by mass of filler material (D)-l was used, and otherwise, in the same manner as in Example 6, a protective film forming film and a protective film forming composite sheet were produced, and evaluation was performed.

[0650] The loss modulus E" of the above protective film forming film was 1.3 MPa.

[0651] The content of the filler material in the solvent-removed thermosetting protective film forming composition was 54.1 mass%. Further, the Tg of the protective film forming composition was 1.7°C.

[0652] The results are shown in Table 1.

[0653]

[0654] From the above results, in Examples 1 to 5 and 9, the gel fraction of the adhesive layer of the support sheet before ultraviolet curing was 90%, and the peelability evaluation of the protective film forming composite sheet was A, and peeling at the interface between the support sheet and the protective film forming film was able to be performed smoothly.

[0655] In Examples 6 to 8, although the gel fraction of the adhesive layer of the support sheet before ultraviolet curing was 50%, the Tg of the protective film forming film was 3°C or higher, and the peelability evaluation of the protective film forming composite sheet was A or B. In Example 8, the peeling evaluation was slightly poor, but all of the protective film forming composite sheets were able to be peeled at the interface between the support sheet and the protective film forming film.

[0656] In contrast, for the protective film forming composite sheets of Comparative Examples 1 and 2, the gel fraction of the adhesive layer of the support sheet before ultraviolet curing was 50% in each, and the Tg of the protective film forming film was less than 3°C in each. In addition, the loss modulus E" of the protective film forming film at 23°C was less than 3 MPa. As a result, the peelability evaluation of the protective film forming composite sheet was C, and peeling could not be performed at the interface between the support sheet and the protective film forming film, and peeling occurred at the interface between the protective film forming film and the adherend.

[0657] Industrial applicability

[0658] The present application can be utilized in the manufacture of semiconductor devices.

Claims

1. A composite sheet for protective film formation, comprising a substrate, and a protective film formation film and an energy ray-curable adhesive layer being stacked in this order on one surface of the substrate in contact with each other, the adhesive layer contains an acrylic resin, the protective film formation film contains a compound having an energy ray-curable group and a weight average molecular weight of 100,000 to 2,000,000, or a compound having an energy ray-curable group and a weight average molecular weight of 100 to 80,000, a gel fraction of the adhesive layer is 80% or more, the compound having an energy ray-curable group and a weight average molecular weight of 100,000 to 2,000,000 is an acrylic resin obtained by reacting an acrylic polymer having a functional group capable of reacting with a group possessed by another compound and an energy ray-curable compound having a group capable of reacting with the functional group and an energy ray-curable group, the compound having an energy ray-curable group and a weight average molecular weight of 100 to 80,000 is an acrylate compound having a (meth)acryl group, an epoxy resin having an energy ray-curable group, or a phenol resin having an energy ray-curable group.

2. A composite sheet for protective film formation, comprising a substrate, and a protective film formation film and an energy ray-curable adhesive layer being stacked in this order on one surface of the substrate in contact with each other, the adhesive layer contains an acrylic resin, the protective film formation film contains a compound having an energy ray-curable group and a weight average molecular weight of 100,000 to 2,000,000, or a compound having an energy ray-curable group and a weight average molecular weight of 100 to 80,000, a gel fraction of the adhesive layer is 20% or more and less than 80%, a glass transition temperature of the protective film formation film is 3°C or more, the compound having an energy ray-curable group and a weight average molecular weight of 100,000 to 2,000,000 is an acrylic resin obtained by reacting an acrylic polymer having a functional group capable of reacting with a group possessed by another compound and an energy ray-curable compound having a group capable of reacting with the functional group and an energy ray-curable group, the compound having an energy ray-curable group and a weight average molecular weight of 100 to 80,000 is an acrylate compound having a (meth)acryl group, an epoxy resin having an energy ray-curable group, or a phenol resin having an energy ray-curable group.

3. The composite sheet for protective film formation according to claim 1, wherein a glass transition temperature of the protective film formation film is 3°C or more.

4. The composite sheet for protective film formation according to any one of claims 1 to 3, wherein a loss modulus of the protective film formation film at 23°C is 3 MPa or more.

5. The composite sheet for protective film formation according to any one of claims 1 to 3, wherein the protective film formation film contains a filler material (D), a content of the filler material (D) in the protective film formation film is 50% by mass or more with respect to a total mass of the protective film formation film.

6. The composite sheet for protective film formation according to claim 1 or 2, wherein The compound having an energy ray-curable group and a weight average molecular weight of 100 to 80,000 is an acrylate compound having a (meth)acryloyl group, or a phenol resin having an energy ray-curable group. The compound having an energy ray-curable group and a weight average molecular weight of 100 to 80,000 is an acrylate compound having a (meth)acryloyl group, or a phenol resin having an energy ray-curable group.

Images